Gilbert Imlay (9 February 1754 – 20 November 1828) was an officer in the American Revolutionary War, a businessman and an author. He had a brief affair with Mary Wollstonecraft that resulted in the birth of a daughter, Fanny Imlay.
Imlay served in the Revolutionary War as an officer of the New Jersey Line. After the war, Imlay traveled to Kentucky to speculate in land. There he swindled a number of people, including Daniel Boone, who was then working as a surveyor, by agreeing to buy lands but then reselling the land without paying the original purchaser. Warrants were issued for Imlay's arrest, but he eluded his creditors and moved to England in 1786.
Imlay's A Topographical Description of the Western Territory of North America was published in London in 1792, which in subsequent editions included the adventures of Daniel Boone (written by John Filson) as an appendix. With Wollstonecraft's assistance, Imlay also tried his hand at novel-writing, publishing The Emigrants in 1793. In 1793, during the French Revolution, he became a diplomatic representative of the United States to France while at the same time pursuing his own business interests. At the time the British were blockading the French ports and he profited by running that blockade. This is where he met Mary Wollstonecraft. In order to sheild her from the dangers of the Revolution, Mary registered at the American Embassy as Imlay's wife, though they never actually married. After the birth of their daughter, Fanny, Mary followed him to Paris. He returned almost immediately to London, leaving Fanny and Mary alone in Paris. She eventually joined him in London, and after returning home from Scandinavia following an important and sensitive business venture Imlay sent her to take care of, Wollstonecraft discovered that Imlay was living with an actress. This effectively ended their relationship.