For nearly 40 years, Western Christianity had no idea which of three men was the real Pope

After a disputed 1378 papal election, rival claimants set up competing papacies in Rome and Avignon, and a council meant to end the split in 1409 only made it worse by electing a third pope instead of resolving anything. European kingdoms picked sides along political lines, splitting the Church's loyalty for a generation. The chaos only ended at the Council of Constance in 1417, which deposed or forced out all three claimants.

— Catholic Church historical records, Western Schism — 1378-1417