John Ker (planter)

John Ker (1789–1850) was an American surgeon, planter, and politician in Louisiana. Together with several major Mississippi planters, in the 1830s Ker co-founded the Mississippi Colonization Society (MCS), promoting the removal of free people of color to a colony in West Africa (which later became part of Liberia). The MCS modeled itself after the American Colonization Society, the national organization for which Ker later served as a vice president.

Born in North Carolina, where his father was the first president of the new state university, Ker moved with his family as a youth to Mississippi after 1817, when his father was appointed to the state supreme court. He went to medical school in Philadelphia, Pennsylvania and returned to the South. A surgeon in the War of 1812 and Creek War, Ker was also a slaveowner and owned a cotton plantation in Louisiana. As a planter, he likewise served in the Louisiana state house.