NY Times: 150th anniversary of the US Civil War: When Cotton Was King

An early opponent of slavery was Rufus King.

He was a delegate for Massachusetts to the Continental Congress. He also attended the Constitutional Convention and was one of the signers of the United States Constitution on September 17, 1787, in Philadelphia, Pennsylvania. He represented New York in the United States Senate, served as Minister to Britain, and was the Federalist candidate for both Vice President (1804, 1808) and President of the United States (1816). - Wikipedia

His residence is a park in New York City in Jamaica, Queens that I've worked on the archeology of a number of times. As I recall someone discovered in the 1976 bicentennial that former VP Aaron Burr had been in Tishomingo, Mississippi after the duel in New Jersey that killed Alexander Hamilton, not plotting "secession" as charged. NY Times Facebook entry.