The Yale Political Union (YPU) is a debate society at Yale University, founded in 1934 by Professor Alfred Whitney Griswold. It was modeled on the Cambridge Union and Oxford Union and the party system of the defunct Yale Unions of the late nineteenth and early twentieth centuries, which were in turn inspired by the great literary debating societies of Linonia and Brothers in Unity. Members of the YPU have reciprocal rights at sister societies in England. The Union is the central forum for political discussion and activism at Yale, and was Yale's largest student organization.