The Yom Kippur balls were countercultural, antireligious festivities held by Jewish anarchists and socialists on Yom Kippur, the holiest day of the Jewish year and day of atonement. Revelers sang, danced, ate, and heard speeches from famous anarchists. The tradition began in England in 1888 and, under the Pioneers of Liberty, recurred annually from New York the year after. By 1891, six other American cities held their own balls.