Martín Jacobo Thompson (1777–1819) was an Argentine patriot, who had an active participation during the English invasions, and the Revolution of May.

[1] Martín Jacobo Thompson was educated at the Royal College of San Carlos, and also in London, England.

[2] Thompson had participated in the defense of the city during the British invasion in Montevideo, where he was wounded, and in Rio de la Plata, where captured several enemy brigs,[clarification needed] being promoted to the rank of ensign of the Spanish Armada.

That year, he was appointed by the Supreme Director, Ignacio Álvarez Thomas, to a diplomatic mission to United States.

However, Madison was on vacation, so Thompson decided to travel to New York City, where he started negotiations for the purchase of war material.