Events of the Year 1259
The year 1259 (MCCLIX) was a common year that commenced on a Wednesday according to the Julian calendar.
By Place
Europe
- September – The Battle of Pelagonia takes place, where the Empire of Nicaea triumphs over the Principality of Achaea, setting the stage for the reconquest of Constantinople in 1261.
- December 4 – An agreement known as the Treaty of Paris is reached between King Louis IX of France and King Henry III of England, where Henry renounces his claims to French-controlled lands, including Normandy, in exchange for Louis withdrawing support for English rebels.
- The renowned frescoes of the Boyana Church in Bulgaria are completed, with the church and its murals later recognized as a UNESCO World Heritage Site.
- The German cities of Lübeck, Wismar, and Rostock form a pact to protect against pirates in the Baltic Sea, laying the groundwork for the future Hanseatic League.
- Nogai Khan leads a second Mongol Golden Horde assault against Lithuania and Poland.
Asia
- August 11 – During a siege on the Song dynasty city of Fishing Town in Chongqing, Möngke Khan, the Mongol Great Khan, passes away. His death triggers a succession crisis within the Mongol Empire, leading to a civil war.
- In the midst of conflict with the Mongols, Chinese official Li Zengbo reports that the city of Qingzhou is producing 1,000 to 2,000 iron-cased gunpowder shells monthly to be sent to Xiangyang and Yingzhou.
- The kingdom of Lannathai is established in northern Thailand by King Mangrai.
- The Goryeo Kingdom in Korea capitulates to the invading Mongol forces.
- Two important era changes occur: the Kaiqing era begins and ends in the Northern Song dynasty, while the Shōka era concludes and the Shōgen era commences in Japan.
Births
- February 25 – Infanta Branca of Portugal, daughter of King Afonso III of Portugal and Urraca of Castile (d. 1321)
- March 25 – Andronikos II Palaiologos, Byzantine emperor (d. 1332)
- Pietro Cavallini, Italian painter (d. 1330)
- Demetre II of Georgia (d. 1289)
- Richard Óg de Burgh, 2nd Earl of Ulster (d. 1326)
Deaths
- January – Matilda II, Countess of Boulogne, ruler of Boulogne, queen consort of Portugal (b. 1202)
- February 7 – Thomas, Count of Flanders
- May 29 – King Christopher I of Denmark (b. 1219)
- July 21 – Gojong of Goryeo
- August 11 – Möngke Khan of the Mongol Empire
- October 7 – Ezzelino III da Romano, Italian ruler
- November 18 – Adam Marsh, English scholar and theologian
- Date Unknown – Matthew Paris, English chronicler