 His rise to prominence in the Patriot cause followed Parliament's passage of the Boston Port Act in 1774.At a public meeting held in Philadelphia on May 20, 1774, Wharton was chosen as a member of the Committee of Correspondence, and later was one of twenty-five citizens who formed the Committee of Safety, Pennsylvania's governing body in the early days of the Revolution.On July 24, 1776, he became president of that body.