Franz Jakob Lefort (Франц Яковлевич Лефорт in Russian) (December 23, 1655 – March 2(12), 1699) was a Russian military figure of Swiss Huguenot origin, general admiral (1695), and close associate of Tsar Peter the Great.
Franz Lefort, born in Geneva, came from a merchant family. He began his military career in the French and Dutch armies. In 1675 Lefort arrived in Russia in the company of the Prussian Colonel Jacob van Frosten in order to find employment with the Russian army. In February 1676 he came to Moscow, but military officials turned him down. The Posolsky Prikaz listed him as a visiting foreigner. Lefort settled in the so-called Nemetskaya sloboda in Moscow, where he would gain respect among other distinguished foreigners. In July 1678 he once again applied for service in the tsarist army. Accepted with the rank of captain, Lefort then went to one of the fronts during the Russo-Turkish War of 1676-1681. In early 1679 he was ordered to join the Kiev garrison under the command of Prince Vasily Galitzine and General Patrick Gordon. Upon his return to Moscow from a short trip to Geneva in 1683, Lefort carried out various diplomatic assignments until the fall of 1685.