John Adams Dix was born in 1798 in Boscawen, New Hampshire. He attended Philips Exeter Academy and the University of Montreal (Canada).Dix served in the War of 1812 and remained in the military until 1828, when he retired with the rank of captain. During that time, he studied law and was admitted to the bar in Washington, D.C. (1820). In 1826, President John Quincy Adams tapped him to serve as his special messenger to Denmark.

By 1828, Dix had returned to the United States and settled in New York. From 1831 to 1834, he served as adjutant-general of New York before becoming secretary of state and superintendent of public schools. Dix joined the Democratic Party in 1841, and by 1842 he had secured membership to lower house of the New York state assembly. Two years later, he filled a vacancy in the U.S. Senate, where he served from 1845 until 1849.

Dix decided not to run for reelection in 1848, choosing instead to campaign as the Free-Soil candidate for New York’s gubernatorial election. Following his loss, he remained with the Democratic Party and, in 1853, became assistant treasurer of the United States in New York at the request of President Franklin Pierce.

Dix supported James Buchanan’s bid for the presidency in 1856 and was rewarded with the postmastership of New York, where he served from May 1860 to January 1861. At that time, and with two months remaining in Buchanan’s term, Dix became secretary of the treasury following the resignation of Howell Cobb. He then returned to New York, where he became involved in raising and organizing regiments for the Union army, eventually serving as commander of the Department of the East.

Following the war, Dix served as chief naval officer of the port of New York until President Andrew Johnson appointed him U.S. minister to France. Dix remained in Paris from 1866 to 1869. Upon returning to the United States, Dix, though a Democrat, was nominated by the Republicans as their nominee for the governor of New York. He won that election and served from 1873 to 1875 before being defeated in his reelection efforts in 1874. He also failed in his bid to become mayor of New York City in 1876. John Adams Dix died in 1879.