Foster moved to Washington, D.C., under President
Ulysses S. Grant, and had a summer home in
Henderson Harbor, New York. As a reward for his political service after the Republican Party split in 1872 as a result of scandals and rampant corruption in Grant's first administration, which even reached Vice President
Schuyler Colfax and had caused reformers to nominate
Horace Greeley in futile opposition to Grant's second term, successive Republican Presidents Grant,
Rutherford B. Hayes and
James A. Garfield appointed Foster the
U.S. Ambassador to Mexico (1873–1880), then
to Russia (1880–1881). President
Chester A. Arthur made Foster the
United States Ambassador to Spain (1883–1885). In
Benjamin Harrison's administration, Foster served as a State Department "trouble shooter" before becoming
Secretary of State for the final six months of Harrison's term (from June 29, 1892, to February 23, 1893). As such, Foster replaced
James Gillespie Blaine, who had succumbed to
Bright's disease, of which he later died. As Secretary of State, Foster "helped direct the overthrow of the Hawaiian monarchy." After leaving public office, Foster remained in Washington and invented a new type of legal practice, lobbying for large "corporations seeking favors in Washington and chances to expand abroad." 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. In 1903, Foster published
American diplomacy in the Orient, followed in 1904 by
Arbitration and the Hague Court. In 1906, he wrote
The practice of diplomacy as illustrated in the foreign relations of the United States. Foster wrote many other books. He wrote the introduction of the first version of
The Memoirs of Li Hung Chang, which was later revealed to be a forgery. ==Family==