1278

Events

• May 8 – Emperor Duanzong of Song China dies of illness and is succeeded by his brother Zhao Bing, who became Emperor Bing of Song. Meanwhile, the international armed forces under the Mongol leader Kublai Khan are drawing closer to the remnants of the Song court. A year later at the Battle of Yamen the Song Dynasty would cease to exist, incorporated into the Yuan Dynasty of China.
• August 26 – Battle of Marchfield: Kings Rudolph I of Germany and Ladislaus IV of Hungary defeat King Otakar II of Bohemia in a match of over 80,000 men and the largest battle of knights in the Middle Ages. The battle ends a power struggle between Rudolph and Otakar over the fate of central Europe, and Rudolph's Habsburg family will continue to rule Austria and other captured territories until the end of World War I in 1918.
• The independence, boundaries, and political structure of Andorra are agreed to by the Spanish Bishop of Urgell and the French Count of Foix.
• End of the so-called War of the Cow in what will become Wallonia (it had begun in 1275).
• The earliest known written copy of the Avesta, a collection of ancient sacred Persian Zoroastrian texts previously passed down orally, is produced.
• An edict by Pope Nicholas III requires all Jews to attend conversion sermons.
• The Japanese era Kenji ends, and the Koan era begins.

Births

• Constantine III of Armenia (d. c. 1310)
• Ferdinand of Majorca (d. 1316)
• Philip I of Taranto (d. 1332)

Deaths

• February 10 – Margaret II, Countess of Flanders (b. 1202)
• May 1 – William II Villehardouin
• May 8 – Emperor Duanzong of China (b. 1268)
• June 30 – Pierre de la Broce, French courtier
• August 26 – King Otakar II of Bohemia
• Al-Nawawi, Distinguished Islamic Scholar (b. 1233)
• Ulrich von Liechtenstein, knight, politician, and minnesinger (b. 1200)
• Nicola Pisano, Italian sculptor