John T. Hoffman was born in Sing Sing (Ossining), the only son of Jane Thompson Hoffman and Dr. Adrian K. Hoffman, a respected physician who served as village president five separate times. He was educated at the Mount Pleasant Military Academy and Union College, graduating at age 18, then studied law with General Aaron Ward and Judge Albert Lockwood of Sing Sing and was admitted to the bar on his 21st birthday. He moved to New York City to practice law in 1850 and over the next 10 years built a reputation and popularity that carried him into politics. After joining the Tammany Society in 1859, he was elected in 1860 to the first of two terms as Recorder of the City of New York, becoming the youngest man ever to hold that post. His performance of his duties as criminal judge of New York during the Civil War draft riots brought him prominence. He was elected mayor of New York City twice, in 1865 and 1867, and during his second term was elected governor, resigning as mayor to serve two terms from 1869 to 1872. Though regarded as an upright man, he could not separate himself from the scandals of Tammany Hall under Boss Tweed, and his reputation did not survive that association. His name had been advanced as a possible presidential candidate in 1872, but he withdrew from public life at the close of his second gubernatorial term at only 44 years old. He died at age 60 while vacationing in Germany.