The eldest child of Rufus King (1755-1827) and Mary Alsop King (1769-1819), John purchased King Manor from his father’s estate in 1827 and continued to use the property as a working farm. John followed in his father’s footsteps into politics and was elected twice to the New York State Assembly and Senate, where he spoke out against the 1840 “gag rule” that existed to stop the receipt of abolitionist petitions to Congress.

In 1849 John was elected to Congress where he established his reputation as an opponent of slavery. He also opposed connecting the admission of free states to the Union with that of slave states. John was Governor of New York from 1857-59, and fought for the arrest of “Blackbirders,” men who seized free black New Yorkers and sold them into slavery. Not surprisingly, the King Manor estate was referred to as the “Governor’s House” and retained this name well into the 20th century. John was instrumental in the formation of the Republican Party and cast his vote as an elector-at-large for Abraham Lincoln in 1860.