1378Centuries: 13th century - 14th century - 15th century
- March - John Wyclif tried to gain public favour by laying his theses before parliament, and then made them public in a tract. He appeared before Simon of Sudbury at the episcopal palace at Lambeth to defend himself.
- April 9 - Pope Urban VI (Bartolomeo Prignano, archbishop of Bari) elected. In the Great Schism the papacy moves from Avignon to Rome, ending the Avignon Papacy.
- September 20 - Unhappy with Pope Urban's behavior, a group of cardinals meet at Fondi and elect Clement VII antipope.
- Dmitri Donskoi of Vladimir defeated a small Mongol army.
- Lorenzo Ghiberti, a sculptor and metal smith.