1290

1290 (MCCXC) was a common year starting on Sunday of the Julian calendar, the 1290th year of the Common Era (CE) and Anno Domini (AD) designations, the 290th year of the 2nd millennium, the 90th year of the 13th century, and the 1st year of the 1290s decade. As of the start of 1290, the Gregorian calendar was 7 days ahead of the Julian calendar, which was the dominant calendar of the time.

• March 1 – The University of Coimbra is founded in Lisbon, Portugal by King Denis of Portugal; it moves to Coimbra in 1308.
• July 18 – King Edward I of England banishes all Jews (numbering about 16,000) from Britain; Jews traditionally hold that this event occurs on Tisha B'Av, a sorrowful Jewish holiday.
• August 1 – The country of Wallachia is founded (traditional date).
• December – The twelve Eleanor crosses are erected between Lincolnshire and London in England as King Edward I mourns the death of his queen consort Eleanor of Castile.
• Construction of Llandaff Cathedral is completed in Cardiff, Wales, 170 years after it was begun.
• The Mongol Empire invades the Bessarabia region of Moldavia.
• The second of the Statutes of Mortmain are passed under king Edward I of England, which prevents land from passing into possession of the church. The statute Quia Emptores is also passed, reforming the feudal system of land leases and allowing the sale of fee simple estates.
• King Denis of Portugal decrees that Portuguese be the official language of Portugal, replacing classical Latin in that capacity.
• Construction on the Akershus Fortress of Oslo, Norway is begun.