John Watson Foster (March 2, 1836 – November 15, 1917) was an American diplomat and military officer, as well as a lawyer and journalist.

His highest public office was U.S. secretary of state under Benjamin Harrison, although he also proved influential as a lawyer in technically private practice in the international relations sphere.

Instead, Foster attended Harvard Law School, then moved to Cincinnati, Ohio, to begin his legal career.

Foster moved to Washington, D.C., under President Ulysses S. Grant, and had a summer home in Henderson Harbor, New York.

[5] Shortly before the Treaty of Shimonoseki ended the First Sino-Japanese War, Foster tried to convince Yuan Shikai to launch a military coup against the Qing dynasty.

Foster doted on his daughters' grandchildren, regaling them with tales of life on the frontier as well as in foreign lands (of which he retained many curios).

His body was returned to Evansville, Indiana, where it remains in Oak Hill Cemetery, which is listed on the National Register of Historic Places for Vanderburgh County.