1251

1251 (MCCLI) was a common year starting on Sunday of the Julian calendar, the 1251st year of the Common Era (CE) and Anno Domini (AD) designations, the 251st year of the 2nd millennium, the 51st year of the 13th century, and the 2nd year of the 1250s decade. As of the start of 1251, the Gregorian calendar was 7 days ahead of the Julian calendar, which was the dominant calendar of the time.

Millennium:	2nd millennium
Centuries:	12th century – 13th century – 14th century
Decades:	1220s  1230s  1240s  – 1250s –  1260s  1270s  1280s
Years:	1248 1249 1250 – 1251 – 1252 1253 1254

1251 in other calendars

Gregorian calendar	1251 MCCLI
Ab urbe condita	2004
Armenian calendar	700 ԹՎ Չ
Assyrian calendar	6001
Balinese saka calendar	1172–1173
Bengali calendar	658
Berber calendar	2201
English Regnal year	35 Hen. 3 – 36 Hen. 3
Buddhist calendar	1795
Burmese calendar	613
Byzantine calendar	6759–6760
Chinese calendar	庚戌年 (Metal Dog) 3947 or 3887     — to — 辛亥年 (Metal Pig) 3948 or 3888
Coptic calendar	967–968
Discordian calendar	2417
Ethiopian calendar	1243–1244
Hebrew calendar	5011–5012
Hindu calendars
- Vikram Samvat	1307–1308
- Shaka Samvat	1172–1173
- Kali Yuga	4351–4352
Holocene calendar	11251
Igbo calendar	251–252
Iranian calendar	629–630
Islamic calendar	648–649
Japanese calendar	Kenchō 3 (建長３年)
Javanese calendar	1160–1161
Julian calendar	1251 MCCLI
Korean calendar	3584
Minguo calendar	661 before ROC 民前661年
Nanakshahi calendar	−217
Thai solar calendar	1793–1794
Tibetan calendar	ལྕགས་ཕོ་ཁྱི་ལོ་ (male Iron-Dog) 1377 or 996 or 224     — to — ལྕགས་མོ་ཕག་ལོ་ (female Iron-Boar) 1378 or 997 or 225

Events

Europe

• April – The first Shepherds' Crusade, a domestic French uprising in response to events in Egypt during the Seventh Crusade, occurs.
• December 26 – King Alexander III of Scotland marries Margaret, daughter of King Henry III of England, precipitating a power struggle between the two monarchs.
• Andrew de Longjumeau, dispatched two years earlier by King Louis IX of France as an ambassador to the Mongols, meets the king in Palestine, with reports from the Mongols and Tartary; his mission is considered a failure.
• Mindaugas of Lithuania is baptized, in prelude to his crowning as King of Lithuania in 1253.
• Alexander Nevsky signs the first peace treaty between Kievan Rus' and Norway.
• King Conrad IV of Germany invades Italy, but fails to subdue the supporters of Pope Innocent IV.
• The German city of Berlin, founded some fifty years earlier, receives its city charter.
• Ottokar II of Bohemia, later to become King of Bohemia, is elected Duke of Austria.
• The earliest known manuscript of The Proverbs of Alfred, a collection of sayings of England's Alfred the Great, is written.

Asia

• Möngke Khan is elected as the fourth great Khan of the Mongol Empire.
• Carving of the Tripitaka Koreana, a collection of Buddhist scriptures recorded on some 81,000 wooden blocks, is completed.

Births

• Hōjō Tokimune, 8th regent of the Kamakura shogunate (died 1284)

Deaths

• Bohemund V of Antioch
• Peter I, Duke of Brittany (born 1190)
• Eljigidei, Mongol commander of Persia
• Isobel of Huntingdon (born 1199)
• Matthias II, Duke of Lorraine