High Commissioner is the title of various high-ranking, special executive positions held by a commission of appointment.
The English term is also used to render various equivalent titles in other languages.

The Commonwealth
In the Commonwealth of Nations, a High Commissioner is the senior diplomat (generally ranking as Ambassador, above an Envoy) in charge of the diplomatic mission of one Commonwealth government to another. As sixteen Commonwealth members, known as the Commonwealth realms, share the same monarch as Sovereign Head of state (currently Her Majesty Queen Elizabeth II), diplomatic relations between these states are traditionally at a governmental level, and so these governments do not appoint Ambassadors to each other, since Ambassadors are the representatives of one Head of state to another.
A High Commissioner from one Commonwealth realm to another carries a simple and often informal letter of introduction from his Head of government (e.g. Prime Minister) to the head of government (prime minister) of the receiving state, while Ambassadors carry formal letters of credence from their Head of State addressed to the host nation's Head of State. The difference in accreditation is also reflected in the formal titles of Envoys to foreign and Commonwealth states: e.g., British High Commissioners are formally titled "The High Commissioner for Her Majesty's Government in the United Kingdom", whereas British Ambassadors to foreign countries are known as "Her Britannic Majesty's Ambassador"
For historical reasons, High Commissioners are also appointed even in the case of Commonwealth republics and indigenous monarchies (i.e. members who do not share the same person as Monarchic Head of State, as the Commonwealth realms do; most are republics). In this case, letters of commission are usually issued by one head of state and presented to the other. However, some Commonwealth governments may choose to use the more informal method of issuing prime-ministerial letters of introduction, while other governments have opted instead for letters of credence.
Instead of embassies, Commonwealth countries have high commissions' in each other's capitals, although it is possible for a country to appoint a High Commissioner without having a permanent mission in the other country: e.g. the British High Commissioner in Suva, Fiji, is also accredited as High Commissioner to Kiribati, Tuvalu and Tonga. Zimbabwe, as a Commonwealth country, has traditionally had High Commissioners in other Commonwealth countries; when it withdrew from the Commonwealth, it changed the style of its former high commission in London to "The Zimbabwe Embassy" (the old letters can still be seen on the building off Agar Street, Strand, London).
Outside the capital, practice is less standard. Subordinate Commissioners or Deputy High Commissioners may be appointed instead of consuls, and the commissioner's mission may be known as a consulate, commission or deputy high commission. In the former British lease territory Hong Kong, most Commonwealth countries were represented by High Commissioners or commissioners before the colony was handed over to the People's Republic of China in 1997; now they have been replaced by consuls or consuls-general as elsewhere outside the Commonwealth.
Despite the differences in terminology, since 1948 Commonwealth High Commissioners have enjoyed the same diplomatic rank and precedence as ambassadors of foreign Heads of State, and in some countries are accorded privileges not enjoyed by foreign Ambassadors. For example, the British Sovereign receives High Commissioners before Ambassadors, and sends a coach and four horses to fetch new High Commissioners to the palace, whereas new Ambassadors only get two horses. High Commissioners also play a part in important ceremonies of state, such as the annual Remembrance Sunday service at the cenotaph in Whitehall (commemorating Commonwealth countries' war casualties) and royal funerals.

Bilateral diplomacy
The first Dominion High Commissioner was appointed by Canada as its envoy in London in 1880, but the Imperial Government did not appoint High Commissioners to the Dominions, where the crown was already represented by the relevant Governor-general. This began to prove problematic after the First World War when the Dominions demanded a far greater degree of control over their foreign affairs. In Canada matters would come to a head during the King-Byng Affair of 1926.
The Balfour Declaration made at the Imperial Conference of 1926 established that Governors-general in the independent dominions were not the representatives of the United Kingdom government but the personal representatives of the Sovereign, and with the constitutional development of the Dominions and their assumption of control over their own external and foreign relations it became standard for the United Kingdom and the Dominions to exchange high commissioners to each other's governments.
From as early as the 1930s, some Commonwealth members have indicated a preference for the title to be replaced with that of Ambassador, but over the years whenever the issue has been raised, a majority of members has been in favour of keeping the separate title and status of High Commissioner.

Dominions
Historically, in the British Empire (most of which would become the Commonwealth) High Commissioners were envoys of the Imperial Government appointed to manage protectorates or groups of territories not fully under the sovereignty of the British Crown, while Crown colonies (which were British sovereign territory) would normally be administered by a Governor and the most significant possessions, large confederations and the independent Commonwealth Dominions would be headed by a Governor-General.
Cases include:
A High Commission could also be charged with the last phase of a decolonisation, as in the crown colony of the Seychelles (12 November 1970 granted autonomy), where the last Governor, Colin Hamilton Allen (b. 1921 - d. 1993), stayed on as only colonial High Commissioner from 1 October 1975, when self-rule under the Crown was granted, till 28 June 1976 when the archipelago became an independent republic within the Commonwealth

the island of Cyprus, since 12 July 1878 under British administration (previously under Ottoman military rule), Istanbul retained nominal suzerainty until the 5 November 1914 full British annexation; there were 9 incumbents (all but one already knighted) from 22 July 1878 until on 10 March 1925 Cyprus became a crown colony, and the last incumbent stayed on as its first Governor British Colonial usage
As diplomatic Residents (as diplomatic ranks were codified, this became a lower class than Ambassadors and High Commissioners) were also appointed to native rulers, that position could on occasion similarly be filled be a colonial Governor. Thus High Commissioners could be charged with managing diplomatic relations with native rulers and their states (analogous to the Resident Minister), and might have under them several Resident Commissioners or similar agents attached to each state. In present Nigeria:
In certain regions of particular importance, a Commissioner-General would be appointed, to have control over several High Commissioners and Governors, e.g. the Commissioner-General for South-East Asia had responsibility for Malaya, Singapore and British Borneo.

Northern Nigeria, three incumbents 1900-1907, the last of which stayed on as first Governor
Southern Nigeria, three incumbent 1900-1906 (four terms), the last of which stayed on as first Governor. British Protectorates
The role of High Commissioner for Southern Africa was coupled with that of British Governor of the Cape Colony in the nineteenth century giving the colonial administrator in question responsibility both for administering British possessions and relating to neighbouring Boer settlements. The best known of these High Commissioners, Alfred Milner who was named to both positions in the 1890s, is considered responsible by some for igniting the Second Boer War.
Historically, in Southern Africa, the protectorates of Bechuanaland (now Botswana), Basutoland (now Lesotho) and Swaziland were administered as High Commission Territories by the Governor-General of South Africa was also the British High Commissioner for Bechuanaland, Basutoland, and Swaziland until the 1930s, with various local representatives, then by the British High Commissioner (from 1961 Ambassador) to South Africa, who was represented locally in each by a Resident Commissioner.
The British Governor of the crown colony of the Straits Settlements, based in Singapore, doubled as High Commissioner of the Federated Malay States, and had authority over the Resident-General in Kuala Lumpur, who in turn was responsible for the various Residents appointed to the native rulers of the Malay states under British protection.
The British Western Pacific Territories were permanently governed as a group of minor insular colonial territories, under one single, not even full time, Western Pacific High Commissioner (1905-1953), an office attached first to the governorship of Fiji, and subsequently to that of the Solomon Islands, represented in each of the other islands units: by a Resident Commissioner, Consul (representative) or other official (on tiny Pitcairn a mere Chief Magistrate).
Currently, there is still one High Commissioner who also serves in an additional capacity as a Governor: the British High Commissioner to New Zealand ex officio serves as British colonial Governor of the Pitcairn Islands.

Governors doubling as High Commissioners
In the (post-)colonial sense, some other powers had High Commissioners, or rather the exact equivalent in their language

Other (mainly former, colonial) empires & protectorates
Originally the French word Haut Commissaire, or in full Haut Commissaire de la république 'High Commissioner of the Republic', was rarely used for governatorial functions, rather (Lieutenant-)gouverneur(-général) and various lower titles. Exceptions were:
In the later period of decolonisation, the office of High Commissioner in a colony to become an allied nation was intended to become remarkably analogous to the Commonwealth's 'close relationship diplomats' in President General De Gaulle's project for a French Union to match the Commonwealth, but it soon started to fall apart, so they actually just presided over most of the peaceful decolonisation.
While the colonies above were generally artificially carved creations, Haut commissaires also were appointed by Paris to prepare the (de facto) independence of pre-existing monarchies that had formally been French protectorates, such as:
Yet a colony could achieve independence without a High Commissioner, e.g. Guinée (French Guinea).
In one case a French Haut Commissaire was the exact match and colleague of a British High Commissioner: they represented both powers in the south sea condominium (i.e. territory under joint sovereignty) of the New Hebrides, which became the present republic of Vanuatu.
A very special category was the Haut Commissaire as 'liquidator' of a gouvernement-général (the colonial echelon grouping several neighbouring colonies under a Governor-general), notably:
Another use for the title was found in the rare remaining insulara (formerly no longer colonial) overseas possessions, in these cases still functioning:

since 22 March 1907, the colonial Gouverneur of New Caledonia was also appointed as High Commissioner in the Pacific Ocean, to coordinate with the governors of the French Settlements in Oceania and the Governors-general of French Indochina; the French resident commissioner of the Anglo-French condominium Nouvelles Hébrides and the Residents to the island protectorates of Wallis and Futuna were subordinated to him

• once Charles de Gaulle named someone else as High Commissioner for the French Territory of the Pacific and the Far East, January 1941 - 1945: Georges Thierry d'Argenlieu (b. 1889 - d. 1964), while in December 1941 the Vichy (pro-German) government named Jean Decoux (b. 1884 - d. 1963) to the post (who in fact was only responsible for Wallis and Futuna, which was the only Pacific territory not to have rallied to the Free French at that time).
  In Atlantic waters, from 14 September 1939 till September 1943, four French Possessions in the Americas (French Guiana, Guadeloupe and Martinique, all in the Caribbean, as well as Saint-Pierre and Miquelon, off the Canadian coast) were temporarily grouped together (from June 1940 under Vichy France, so remaining on the Allied side). The two consecutive 'High Commissioners in the Antilles' (quite a misleading title: French Guyana is in continental South America, St-Pierre&Miquelon off the Canadian coast, so in North America) held both administrative authority over the local Governors and equivalent officers (rather like a gouverneur général did elsewhere on a permanent basis) and military command in the 'Theater Atlantic West':
  
  
  
  • 14 September 1939 - 14 July 1943 Georges Robert (b. 1875 - d. 1965)
    14 July 1943 - September 1943 Henri Hoppenot (b. 1891 - d. 1977)
    Algérie (Algeria), once similar to Tunis, but transformed into a French popular colony (most of the time under its own governor-general; then a messy period as native and immigrated European interests were irreconcilable), got its only High commissioner on 19 March 1962: Christian Fouchet (b. 1911 - d. 1974), until its 3 July 1962 independence from France (Algerian State; 25 September 1962 People's Democratic Algerian Republic ruled by the FLN, the former armed revolt)
    in present Benin, since 13 October 1946 Dahomey overseas territory, on 4 December 1958 granted autonomy as Republic of Dahomey, the last (acting) governor, René Tirant (b. 1907), stayed on as only High commissioner till the 1 August 1960 independence
    Chad, since 27 October 1946 an overseas territory of France (part of AEF colony) under its own Governor, shortly after it was on 28 November 1958 granted autonomy as Republic of Chad, had a single High Commissioner from 22 January 1959: Daniel Marius Doustin (b. 1920) until its 11 August 1960 independence from France.
    Congo-Brazzaville (variously named, often Middle Congo) had a single High commissioner, a bit after it was granted on 28 November 1958 autonomy (as Republic of Congo), 7 January 1959 - 15 August 1960: Guy Noël Georgy (b. 1918 - d. 2003) after many Lieutenant governors since 11 December 1888 (under the governor-general of AEF, except the several cases when he governed the French Congo personally); afterwards it was an independent republic
    Côte d'Ivoire (Ivory Coast) had two High Commissioners since it was granted autonomy as republic of Ivory Coast:
    
    
    
    • 4 December 1958 - 15 July 1960 Ernest de Nattes (b. 1908), the last of the long list of governors since 10 March 1893 (colony till 27 October 1946, then overseas territory)
      15 July 1960 - 7 August 1960 Yves René Henri Guéna (b. 1922); thereafter it was an independent republic
      Gabon had two High Commissioners since on 28 Nov 1958 autonomy was granted (as Gabonese Republic) to the former overseas territory (since 1946)
      
      
      
      • November 1958 - July 1959 Louis Marius Pascal Sanmarco (b. 1912), also the last of the Governors since 1941 (after various otherwise styled chief executives before; it had since 15 January 1910 been part of French Equatorial Africa, AEF)
        July 1959 - 17 August 1960 Jean Risterucci (b. 1911 - d. 1982); thereafter it was an independent republic
        Mauritania had two High commissioners, after having been a protectorate since 12 May 1903 (under a single military Commandant), from 18 October 1904 the French civil territory of Mauritania under a Commissioner (part of French West Africa (AOF); under its Governor-general in Dakar, Senegal), and since 12 January 1920 a French colony under a Lieutenant governor (many incumbents, again under Dakar), on 28 November 1958 obtaining autonomy (as Islamic Republic of Mauritania):
        
        
        
        • 5 October 1958 - February 1959 Henri Joseph Marie Bernard (b. 1920)
          February 1959 - 28 November 1960 Amédée Joseph Émile Jean Pierre Anthonioz (b. 1913 - d. 1996); since independence from France it had its own President (or a junta chief);
          In Niger, since 13 October 1946 an overseas territory of France (part of French West Africa, see Senegal) under a lieutenant-governor, on 19 December 1958 granted autonomy as Republic of Niger, there was a single High commissioner 25 August 1958 - 10 November 1960: Jean Colombani (b. 1903), i.e. still several months after the formal 3 August 1960 independence whilst there was no President
          In Senegal, since 27 October 1946 an overseas territory of France, which on 25 November 1958 had obtained autonomy (as Republic of Senegal), the last Governor stayed on as first (and only?) Haut commissaire 25 November 1958 - 20 June 1960: Pierre Auguste Michel Marie Lami (b. 1909); meanwhile on 4 April 1959 the Sudanese Republic (now Mali) and Senegal formed the Mali Federation and his term ended at the 20 June 1960 independence of that Mali Federation from France (on 20 August 1960 the Republic of Senegal withdrew from the thus dissolved Mali Federation).
          in French Sudan, an overseas territory of France since 27 October 1946 (earlier a colony; stayed within French West Africa), which on 24 November 1958 obtained autonomy (as Sudanese Republic), there were two High commissioners:
          
          
          
          • 3 November 1956 - 24 November 1958 Henri Victor Gipoulon
            24 November 1958 - 20 June 1960 Jean Charles Sicurani (b. 1915 - d. 1977); during his term on 4 April 1959 this Sudanese Republic and Senegal (cfr. above) united to form the Mali Federation; his office ceased at the 20 June 1960 independence of the Mali Federation from France
            In Upper Volta (since 4 January 1947 a French territory; present Burkina Faso, renamed 4 August 1984), since the 11 December 1958 grant of Autonomy as a 'republic', République de Haute-Volta, there were two High commissioners:
            
            
            
            • 11 December 1958 - February 1959 Max Berthet, who stayed on, having been the last (acting) Governor
              February 1959 - 5 August 1960 Paul Jean Marie Masson (b. 1920), till the Independence from France as Republic of Upper Volta.
              Tunisia, known as the Régence (since 3 June 1955 autonomous), where France had a Resident-general (posted with the Basha bey of Tunis, who once the French protectorate was terminated on 20 March 1956 restyled his realm al-Mamlaka at-Tunisiyya 'Tunisian Kingdom'), in stead got a High commissioner from 13 September 1955 to 20 March 1956: Roger Seydoux Fornier de Clausonne (b. 1908 - d. 1985); in continued shortly as independent monarchy, but on 25 July 1957 became the Tunisian Republic.
              in Afrique Equatoriale Française (French Equatorial Africa, AEF), three High commissioners:
              
              
              
              • 4 April 1957 - 29 January 1958 Paul Louis Gabriel Chauvet (b. 1904), also the last of the long list of Governors-general since 28 June 1908 (before it had five Commissioners-general since 27 April 1886)
                29 January 1958 - 15 July 1958 Pierre Messmer (b. 1916)
                15 July 1958 - 15 August 1960 Yvon Bourges (b. 1921)
                in Afrique Occidentale Française (AOF), i.e. French West Africa, the last of a long list of Governors-general since 1895 stayed on as first of only two High Commissioners:
                
                
                
                • 4 April 1957 - July 1958 Gaston Custin (b. 1903 - d. 1993)
                  July 1958 - 22 December 1958 Pierre Messmer (b. 1916)
                  In French Polynesia it is the title of the representative of the French republic in the overseas territory (restyled 'overseas collectivity' in 2003, 'overseas country' on 27 February 2004) since 13 July 1977 (until 14 September 1984 he also presided the local council of ministers, the that got its own president, as the legislature already had)
                  In New Caledonia (Nouvelle Calédonie in French, colonised in 1853; its Governors had been High Commissioners in the Pacific Ocean from 22 March 1907, see above) the title (commonly corrupted to Haussaire) was chosen for the chief executive on 19 December 1981, when it was an overseas territory (since 1946), even before autonomy was granted on 18 November 1984, and maintained after its status was changed on 20 July 1998 to the unique French collectivité sui generis; he represents the Paris government, while there are a native legislature and government. French
                  On 30 July 1922, the Hellenic kingdom (Greece) declared Smyrna (the Anatolian Izmir district, occupied by Greece since 12 May 1919) a protectorate. Until on 9 September 1922 Greece restores Smyrna to Turkey after defeat of Greek forces, it had a Greek High Commissioner (21 May 1919 - 8 September 1922): Aristeidis Stergiadis (b. 1861 - d. 1950)
                  
                  Greek
                  
                  while only various military commanders and since 1916 a Secretary for Civil Affairs in Albania (Ugo Capialbi) had acted for Rome since Italy invaded on 27 December 1914 (occupying Valorë and parts of Southern Albania; on 3 June 1917 Albanian independence under an Italian protectorate was declared by Italy, opposed by most Albanians; adding in November 1918 the former Austro-Hungarian occupied areas to the Italian zone) only since in 1919 an Albanian provisional government recognized by Italy as the legal government of the protected zone, consecutive High Commissioners for the Crown were appointed until Italy effectively withdraw its troops on 3 September 1920 (as agreed on 22 August 1920 when formally recognizing the total independence of Albania):
                  
                  
                  
                  • 1919 - 1920 ....
                    1920 Castoldi
                    1920 - 3 September 1920 Gaetano Conti Manzoni
                    two incumbents appointed by the kingdom in Fiume (a former Austrian province; now Rijeka, in Croatia), after an extraordinary commissionary, in the 31 December 1920 declared, short-lived "Independent State of Fiume", until the accession of its first President
                    
                    
                    
                    • 13 June 1921 - 1921 Antonio Foschini (b. 1872 - d. 19..)
                      1921 - 5 October 1921 Luigi Amantea (b. 1869 - d. 19..)
                      in Slovenia, which after 6 - 17 April 1941 Italian-German occupation, was on 17 April 1941 partitioned between Italy, Hungary and Germany, the Italian portion was named province of Lubiana, from 3 May 1941 under a Civil Commissioner, from 3 May 1941 restyled the first of two High Commissioners:
                      
                      
                      
                      • 18 April 1941 - 1942 Francesco Saverio Grazioli (b. 1869 - d. 1951)
                        1942 - 1943 Giuseppe Lombrassa (b. 1906 - d. 1966) Italian
                        
                        Cabo Verde (Cape Verde) once: 30 December 1974 - 5 July 1975 Vicente Almeida d'Eça
                        São Tomé and Príncipe had a single High Commissioner, from 18 December 1974 (three days before the formal granting of autonomy): António Elísio Capelo Pires Veloso, actually the last of many governors (since 1753, before both islands were separate), staying on until it became an independent republic on 12 July 1975 Portuguese
                        Alto comisario was the Spanish title of the official exercing the functions of a governor in the following colonial possessions:
                        The title Alto Comisario was also used for the representative of Spain in its protectorate zone within the Sherifan sultanate of Morocco (most of the country was under French protectorate), known as el Jalifato after the khalifa (Jalifa in Spanish), the Sultan's fully mandated, princely Viceroy in this protectorate, to which the High Commissioner was formally accredited, but whose senior he was in reality. In 1934 - 1956 the Governors of the Western Sahara (which from 27 November 1912 were also Governors-general of Spanish West Africa) were subordinated to him. The office itself was however filled by the governors of Spanish West Africa from 1939 to 1956.
                        
                        Equatorial Guinea had three consecutive High Commissioners:
                        
                        
                        
                        • 15 December 1963 - 1964 Francisco Núñez Rodríguez (b. 1902 - d. 1972), also the last of many Governors since 7 June 1494
                          1964 - 1966 Pedro Latorre Alcubierre
                          1966 - 12 October 1968 Víctor Suances Díaz del Río; his term ended when it became an independent republic Spanish
                          
                          while the Dominican Republic was under a 28 March 1905 - 1941 U.S. protectorate, it had first various native regimes, then US military Governors 29 November 1916 - 24 July 1922, and just before it again had the first of its own Presidents on 21 October 1922, a single U.S. High Commissioner, September 1922 - 1924: Benjamin Sumner Welles, its last 'guardian'
                          also in Haiti, the other (western) half of the island of Hispaniola, 28 July 1915 - 1936 under U.S. protectorate, after five U.S. Military Commanders, there was a single High Commissioner, 11 February 1922 - 16 November 1930: John Henry Russell, Jr. (b. 1872 - d. 1947), next three Envoys Extraordinary and Ministers Plenipotentiary till 15 August 1934
                          the Commonwealth of the Philippines (since 13 August 1898 a U.S territory), since it got that more autonomous status on 15 November 1935, had the following U.S. High Commissioners:
                          
                          
                          
                          • 15 November 1935 - 1937 Frank William Murphy (b. 1890 - d. 1949), also the last of a series of Governors-general
                            1937 - 1939 Paul Vories McNutt (1st time) (b. 1891 - d. 1955)
                            1939 - 7 September 1942 Francis Bowes Sayers (from 24 December 1941 in U.S. exile during Japanese military occupation) (b. 1885 - d. 1972)
                            7 September 1942 - 4 July 1946 Paul Vories McNutt (2nd time) (to August 1945 in U.S. exile during Japanese military occupation); his termed ended with the official independence of the new republic (the office was not affected by the 14 October 1943 - 17 August 1945 Nominal independence as Republic of the Philippines)
                            Okinawa and Ryukyu Islands (Japanese archipelago), next only Okinawa island (formerly a kingdom), had six U.S. incumbents, from 4 July 1957:
                            
                            
                            
                            • James Edward Moore (b. 1902 - d. 1986), the last Deputy governor and Commanding General Ryukyu Islands Command;
                              1 May 1958 - 12 February 1961 Donald Prentice Booth (b. 1902 - d. 1993)
                              16 February 1961 - 31 July 1964 Paul Wyatt Caraway (b. 1905 - d. 1984)
                              1 August 1964 - 31 October 1966 Albert Watson II (b. 1909 - d. 1993)
                              2 November 1966 - 28 January 1968 Ferdinand Thomas Unger (b. 1913 - d. 1999); on 21 November 1967 most Ryukyu Islands (except Okinawa) were restored to Japan
                              28 January 1968 - 15 May 1972 James Benjamin Lampert (b. 1914 - d. 1978); only on 15 May 1972 Okinawa reverted to Japanese sovereignty as a prefecture, so the office, now of US High Commissioner on Okinawa, ceased; so did the US Civil Administrators that had been appointed since 18 July 1962 alongside them. High Commissioners as Extraordinary Government Agents
                              In France, a high commissioner, in French haut-commissaire, is a civil servant appointed by the President of France to some high level position within France:
                              
                              The High commissioner for atomic energy is the head of the CEA
                              cfr. Haute Autorité. Domestic High Commissioners
                              
                              Multilaterally mandated
                              Often the main/locally concerned members of an alliance would not set up a joint occupation authority (as in Italy after the Nazi defeat) but simply each appoint one for each of the zones into which they physically divided amongst themselves an occupied state or territory, e.g. after World War II:
                              
                              Even shortly before on 8 December 1918 the Allied occupation of the Bosporus, the Dardanelles, the eastern coast of the Sea of Marmara, the islands of Imros, Lemnos, Samothrace and Tenedos and 15 km deep into eastern and the eastern shores; entire area demilitarized (Zone of the Straits; complemented 16 March - 10 August 1920 as the allies occupy the Ottoman capital Istanbul) was a military fact, in November 1918 a double post was created: until the termination of allied occupation on 22 October 1923, there were at all times one British Senior Allied High Commissioner and one (junior) Allied High Commissioner (incumbents from France, thrice, Italy and the US, each twice).
                              in Austria, until 27 July 1955 when Allied occupation ends, restoring Austrian sovereignty, it was administered as a British Zone (6 consecutive High Commissioners, July 1945), a US Zone (4 incumbents from 5 July 1945), a Soviet Zone (4 from July 1945; only this had first been under a Military Governor from 8 April 1945) and a French Zone (2, from 8 July 1945);
                              in Germany there were also four major occupation zones: the British Zone (after three consecutive Military governors from 22 May 1945, the last stayed on as first of three consecutive High Commissioners 21 September 1949 - 5 May 1955), the US Zone (after five Military governors from 8 May 1945, four High Commissioners 2 September 1949 - 5 May 1955), the Soviet Zone (after a military commander April 1945 - 9 June 1945 who styed as first of three Military governors 9 June 1945 - 10 October 1949, the last of whom stayed on as only Chairman of the Soviet Control Commission 10 October 1949 - 28 May 1953, two High commissioners 28 May 1953 - 20 September 1955) and the French Zone (after a Military commander from May 1945 and a Military governor from July 1945, a single High commissioner 21 September 1949 - 5 May 1955); the Nazi capital, Berlin, enclaved in the Soviet zone, is separately quartered under four military City Commanders; only the small Dutch zone by the border is destined for annexation in 1949, so it is divided up in two districts, each under a landdrost (Tudderenen, attached to the province of (Dutch) Limburg and Elten, attached to Gelderland province), but returned to Germany after compensation payments and minor border corrections on 11 August 1963 Representing an international alliance
                              These 'guardianships' most often were simply awarded to the former colonial power or if that was a loser in the preceding World War, to the 'liberating' Allied victor(s).
                              
                              As the 'world community' became a widely accepted ideal in diplomacy and was embodied first in the League of Nations and later the UNO, these often came to play a key role in extraordinary situations that would earlier probably have been dealt with by states as above, sometimes reflected in the appointment of High Commissioners under their auspices, sometimes just from the same leading powers, sometimes rather from 'neutral' member states.
                              The title of High Commissioner was specifically used for the administrators during the 'emancipation from colonial rule' of League of Nations mandates and United Nations Trust Territories, i.e. non-sovereign states under a 'transitional' regime established under the authority of the League of Nations or the UN, respectively, to prepare them for full independence. Emancipatory administrators under International law
                              
                              Iraq, conquered on the Ottoman Walis by British forces, had four incumbents, after a single civilian Administrator (10 January 1919 - 1 October 1920 Sir Arnold Talbot Wilson), continuing ten years after the accession to the throne and most of the rule of the country's first Malik (King, resigned 23 August 1921 - 8 September 1933) Faysal I (b. 1885 - d. 1933) :
                              
                              
                              
                              • 1 October 1920 - 4 May 1923 Sir Percy Zachariah Cox (b. 1864 - d. 1937)
                                4 May 1923 - October 1928 Sir Henry Robert Conway Dobbs (acting to 15 September 1923) (b. 1871 - d. 1934)
                                October 1928 - 11 September 1929 Sir Gilbert Falkingham Clayton (b. 1875 - d. 1929)
                                3 October 1929 - 3 October 1932 Sir Francis Henry Humphrys (b. 1879 - d. 1971)
                                The British Mandate of Palestine High Commissioners
                                
                                
                                
                                • 01 July 1920 – 1925 Sir Herbert Louis Samuel (1879–1963), until the 1922 establishment of the mandate actually the first civilian who took over, already as High Commissioner, from the three consecutive military administrators since the 1917 conquest by British forces
                                  1925 Sir Gilbert Falkingham Clayton (acting) (1875–1929)
                                  25 August 1925 – August 1928 Herbert Charles Onslow Plumer, Baron Plumer (1857–1932)
                                  August 1928 – 06 December 1928 Sir Harry Charles Luke (acting) (1884–1969)
                                  06 December 1928 – 1931 Sir John Robert Chancellor (1870–1952)
                                  1931 – 1932 Mark Aitchison Young (acting) (1886–1974)
                                  1932 – September 1937 Sir Arthur Grenfell Wauchope (1874–1947)
                                  September 1937 – March 1938 William Denis Battershill (acting) (1896–1959)
                                  03 March 1938 – 03 September 1944 Sir Harold Alfred MacMichael (1882–1969)
                                  03 September 1944 – 21 November 1945 John Standish Surtees Prendergast Vereker, Viscount Gort (1886–1946)
                                  21 November 1945 – 14 May 1948 Sir Alan Gordon Cunningham (1887–1983) League of Nations - Mandate territories
                                  
                                  United Nations
                                  
                                  In Togo, once a German colony, then a League of Nations mandate, * three High commissioners
                                  
                                  
                                  
                                  • 21 September 1956 - 23 March 1957 Jean Louis Philippe Bérard (b. 1910), in fact the last of many Commissioners since 4 September 1916
                                    23 March 1957 - June 1957 Joseph Édouard Georges Rigal (acting)
                                    June 1957 - 27 April 1960 Georges Léon Spénale (b. 1913 - d. 1983); next it was an independent republic.
                                    The UN Trust Territory of the Pacific Islands (originally comprising Marshall Islands, Micronesia, Northern Mariana Islands and Palau), after Allied military occupations, since 18 July 1947, had a dozen incumbents, also presiding over the splitting off of Palau and Marshall Islands in 1980 and the 10 May 1979 granting of autonomy to the Federated States of Micronesia (former Ponape, Truk and Yap districts of the Trust Territory) until on 3 November 1986 the Trust territory was dissolved by the U.S. (a single Director of the Office of Transition stepped in 3 November 1986 - 30 September 1991: Charles Jordan, so a while after the 22 December 1990 proclamation of final independence as the UN Security Council ratifies the termination of US trusteeship). UN Trust territories
                                    
                                    After the former Italian colony of Eritrea had been under victor Britain's administration since 5 May 1941, a specific United Nations administration, under Britain, was installed on 19 February 1951, under a UN High Commissioner, Edoardo Anze Matienzo (Bolivian, b. 1902), whose office ceased on 15 September 1952 when it was Federated with Ethiopia under the sovereignty of the Ethiopian emperor. Representing the world universally
                                    
                                    Lord High Commissioner
                                    List of Canadian High Commissioners to the United Kingdom
                                    High Representative