Francis Philip Fatio (Spanish Francisco Phelipe Fatio; 1724–1811), born in Switzerland, was a soldier for France, a viscount in Sardinia, a merchant in London, and a prominent planter in East Florida during both the British period and the second Spanish period.

[3] In 1771, Francis Fatio moved with his family to East Florida to become the managing partner of New Castle Plantation, which specialized in producing indigo.

During the American Revolution he served as a staff officer with the British Army, stationed in Charleston, South Carolina.

Fatio had disputes with Spanish officials over the proper measurement of corn he sold to the government, his lack of cooperation with government inquiries, and his desire to participate in the trade with Native Americans, which was an official monopoly of Panton, Leslie & Company.

[7] During the transition period of the transfer of East Florida from Britain to Spain, incoming Spanish Governor Vicente Manuel de Zéspedes appointed Francisco Fatio and John Leslie (of Panton, Leslie & Company) to judge disputes between British subjects who were preparing to leave the colony.

Fatio, along with the few other British subjects who were remaining in Florida under the Spanish, bought fixed property cheaply from the departing settlers, often with a promise to forward the proceeds of future sales when prices had improved.

Merchant ships could sail up the St. Johns to Nueva Suiza as well, carrying away products, including timber, from the plantation.

The next year the Fatio family was driven from Nueva Suiza by the Patriot Army, a force of American volunteers who made a filibustering attempt to seize East Florida.

[3] Francis Philip and Maria Fatio's daughter Sophia married George Fleming.