Thomas Buchanan Winthrop (November 11, 1841 – December 25, 1900)[1] was an American philanthropist and lawyer who was prominent in New York society during the Gilded Age.

[6] Through his father's family, he was also descended from the colonial New York merchant and politician Leonard Lispenard.

[3] After Columbia, Winthrop passed the bar exam and began practicing law in New York City until he "inherited a fortune from his father which made him independent.

[8] Bishop Potter appointed Winthrop treasurer of the General Convention of the Episcopal Church, serving for several years.

Together, they were the parents of:[3] Winthrop died on Christmas Day, December 25, 1900, at his residence, 279 Fifth Avenue in New York City.