The Babylonian Captivity

In the 14th century, the papacy moved from Rome to Avignon, France. For decades, you had two popes and Europe divided up as to which of the two popes they would follow. The council of Pisa in the early 15th century attempted to heal the schism but only succeeded in electing a third pope. And so finally, it was the council of Constance around 1415 that met deposed all three popes and healed the papacy. That's the same Council that burned Yan Hus for believing in justification by faith alone.