Immigrated to Maryland (1774), where his half-brother John established him in the carrying trade between France and the West Indies. Traveled to Kentucky (1787) with a letter of introduction from George Washington. Taken captive by Shawnee Indians (1788); released in Detroit.
Moved to Montreal, then to Niagara (1792). First clerk to the surveyor general of Upper Canada (1793). Acting surveyor general (1799, 1802, 1807). Surveyor general (1810). Also served in the legislature.
Son of George Ridout of Dorset, England. Twice married; thirteen children.