John Adams Dix (July 24, 1798 - April 21, 1879) was an American politician from New York. He served as Secretary of the Treasury, U.S. Senator, and Governor. He was also a distinguished Civil War General.
Dix was born in Boscawen, New Hampshire. He joined the Royal Artillery as a military cadet at the age of 14. He served in the United States Army, having attained the rank of captain.
In 1826, Dix married Catherine Morgan, the adopted daughter of Congressman John J. Morgan, who gave Dix a job overseeing his upstate New York land holdings in Cooperstown. John and Catherine moved to Cooperston in 1828, and John practiced law in addition to overseeing the land holdings. Dix was appointed Adjutant General of New York State by Governor Throop, he moved to Albany, New York in 1830, and he served as New York State Secretary of State.
Dix was elected as a Democrat to the United States Senate to fill the vacancy caused by the resignation of Silas Wright, Jr., and served from 1845 to 1849. He was not a candidate for reelection, having become a candidate for Governor. He was an unsuccessful Free-Soil candidate for Governor in 1848.
Later, he was appointed postmaster of the city of New York and served from 1860 to 1861. He was appointed United States Secretary of the Treasury by President James Buchanan in 1861. At the outbreak of the Civil War, he sent a telegram to the Treasury agents in New Orleans ordering that: "If any man pulls down the American flag, shoot him on the spot". Although the telegram was intercepted by Confederates, and was never delivered to the Treasury agents, the text found its way to the press, and Dix became one of the first heroes of the North during the Civil War.
During the American Civil War, as a major general in the Union army, he commanded the Department of Virginia from June 1862 until July 1863, and the Department of the East from July 1863 until April 1865.
He was the United States Minister to France from 1866 to 1869.
He served as the Governor of New York in his seventies, as one of the oldest governors of New York, between 1873 and 1875; he was an unsuccessful candidate for reelection in 1874. He suffered another defeat when he ran for the mayor of New York City in 1876. He died in New York City and was interred in the Trinity Church Cemetery.
He is not to be confused with John Alden Dix, another Governor of New York, who served in the 1910s.
Fort Dix, New Jersey, a United States Army post, is named for Dix, as is Dix, Illinois and several revenue cutters, John A. Dix.