1242

Decades: 1190s 1200s 1210s 1220s 1230s - 1240s - 1250s 1260s 1270s 1280s 1290s

Years: 1237 1238 1239 1240 1241 - 1242 - 1243 1244 1245 1246 1247

• April 5 - During a battle on the ice of Chudskoye Lake, Russian forces rebuff an invasion attempt by the Teutonic Knights.
• Emperor Go-Saga ascends to the throne of Japan.
• Batu Khan establishes the Golden Horde at Sarai.
• Cleves, Germany is chartered as a city.
• Kiel, Germany is chartered as a town.
• The diocese of Warmia, Poland is created.
• The archbishop of Wiesbaden conquers the city from the Duke of Nassau.
• The Mongols invade the Seljuk sultanate.
• German colonists arrive in Bratislava after the Mongols fail to conquer the city.
• Timeline of medicine and medical technology - Ibn Nafis suggests that the right and left ventricles of the heart are separate and describes the lesser circulation of blood.

• George Pachymeres, Byzantine historian
• Prince Munetaka, 6th Kamakura shogun in Japan

• Emperor Juntoku of Japan
• Emperor Shijo of Japan

• Aragon - James I King of Aragon and count of Barcelona (reigned from 1213 to 1276)
• Castile - Ferdinand III, the Saint King of Castile and Leon (reigned from 1217 to 1252)