The Bethlehem Chapel in Prague was built for preaching in Czech, and Jan Hus preached there from 1402 to a congregation of ordinary townspeople. His programme was moral before it was doctrinal: clergy should be poor, benefices should not be sold, and a priest in mortal sin has no business ministering. Behind it lay the writings of John Wyclif, circulating in Bohemia through the university, and behind that a national grievance about German dominance in church and university appointments.
He was excommunicated, went on preaching, and accepted a safe conduct to the Council of Constance in 1414 to defend himself. He was arrested, tried and burned in July 1415, and his ashes were thrown in the Rhine so that nothing would remain to venerate.
Bohemia rose. The distinguishing practice of the movement was giving the cup as well as the bread to the laity, which the council had explicitly forbidden, and the chalice became its emblem, painted on shields and banners. Its programme was set out as the Four Articles of Prague, and the wars that followed saw a small kingdom defeat repeated crusades. A compromise permitted communion in both kinds in Bohemia, and a separate church survived there for two centuries, a full hundred years before Luther. It was ended by force after the defeat at White Mountain in 1620, and the reimposition of Catholicism drove the Unity of the Brethren into exile, from where it grew into the Moravian Church.