1378

Millennium:	2nd millennium
Centuries:	13th century – 14th century – 15th century
Decades:	1340s 1350s 1360s – 1370s – 1380s 1390s 1400s
Years:	1375 1376 1377 – 1378 – 1379 1380 1381

1378 in topic:
Subjects: Archaeology – Architecture –
Art – Literature – Music – Science
Leaders: State leaders – Colonial governors
Category: Establishments – Disestablishments
Births – Deaths – Works

Year 1378 (MCCCLXXVIII) was a common year starting on Friday (link will display the full calendar) of the Julian calendar.

Events of 1378

March – In England, John Wycliffe tries to promote his ideas for Catholic reform by laying his theses before parliament and making them public in a tract. He is subsequently summoned before Archbishop of Canterbury, Simon of Sudbury, at the episcopal palace at Lambeth to defend his actions.
April 9 – Following the death of Pope Gregory XI and riots in Rome calling for a Roman pope, the cardinals, who are mostly French, elect Pope Urban VI (Bartolomeo Prignano, Archbishop of Bari) as the 202nd Pope.

July – Revolt of the Ciompi – discontent wool carders briefly take over the government of Florence. For the first time, a European government represents all social classes.
August 4 – Gian Galeazzo Visconti succeeds his father, Galeazzo II Visconti, as ruler of Milan.
September 20 – Unhappy with Pope Urban's critical attitude towards them, the majority of the cardinals meet at Fondi and elect Clement VII as antipope and establish a rival papal court at Avignon. This split within the Catholic Church becomes known as the Western Schism.
November 10 – Estimated appearance date of Halley's Comet.
November 29 – Charles IV, Holy Roman Emperor, is succeeded by his son, Wenceslaus.

Holy Roman Emperor Charles IV visits his nephew Charles V of France to publicly celebrate the friendship between their two nations.
The Papacy makes a permanent move back from Avignon to Rome, ending the Avignon Papacy.
France, Aragon, Castile and León, Cyprus, Burgundy, Savoy, Naples and Scotland choose to recognise Antipope Clement VII. Denmark, England, Flanders, the Holy Roman Empire, Hungary, northern Italy, Ireland, Norway, Poland and Sweden continue to recognise Pope Urban VI.
Dmitri Donskoi of Moscow & Vladimir resists a small invasion by the Mongol Blue Horde.
Tokhtamysh dethrones Timur Malik as Khan of the White Horde.
Kara Osman establishes the Turkomans of the White Sheep dynasty at Diyarbakır in present-day southeast Turkey.
The Turks capture the town of Ihtiman in west Bulgaria.
Uskhal Khan succeeds his father, Biligtü Khan, as ruler of the Yuan Dynasty in Mongolia.
Balša II succeeds his father, Durađ I, as ruler of Zeta (now Montenegro).
Tai Bian succeeds Zhao Bing Fa as King of Mong Mao (now northern Myanmar).
Da'ud Shah succeeds his assassinated nephew, Aladdin Mujahid Shah, as Bahmani Sultan in present-day southern India. Da'ud Shah is assassinated in the same year and is succeeded by Mohammed Shah II.
Sa'im al-Dahr is hanged for blowing the nose off the Sphinx.

August 16 – Hongxi Emperor of China (died 1425)
October 24 – David Stewart, Duke of Rothesay (died 1402)
December 31 – Pope Callixtus III (died 1458)
date unknown
- Vittorino da Feltre, Italian humanist (died 1446)
- Lorenzo Ghiberti, Italian sculptor and metal-worker (died 1455)
- John Hardyng, English chronicler (died 1465)

February 6 – Jeanne de Bourbon, queen of Charles V of France (born 1338)
March 27 – Pope Gregory XI
July – Owain Lawgoch, titular Prince of Wales – assassinated (born circa 1330)
August 4 – Galeazzo II Visconti, Lord of Milan (born c. 1320)
August 16 – San Rocco di Venezia, patron saint of pestilence (born 1340)
November 29 – Charles IV, Holy Roman Emperor (born 1316)