1200
The Proleptic Gregorian calendar called it a century leap year.
Events
By place
Europe
- Spring - Boniface I, Marquis of Montferrat, sends envoys to Venice, Genoa and other city-states to negotiate a contract for transport to the Levant. Meanwhile, Boniface and various nobles are mustering an expeditionary army at Paris. On February 23, Baldwin IX, count of Flanders and his brother Henry of Flanders take the cross at Bruges, and agree to take part in the Fourth Crusade called by Pope Innocent III.
- May 22 - The Kings John of England and Philip II of France, sign a peace treaty at Le Goulet, an island in the middle of the Seine River, near Vernon in Normandy. The agreement recognizes John as overlord of most of the English owned lands in France, but John has to give Philip the lands of Norman Vexin and Évreux and a large sum of money – a "relief" payment for recognition of John's sovereignty of Brittany.
- August 25 - Eager to make peace with Aymer Taillefer, count of Angoulême, John marries 15-year-old Isabella of Angoulême at Bordeaux. In order to remarry, John needs to abandon his first wife, Isabella of Gloucester. John accomplishes this by arguing that he has failed to get the necessary papal dispensation to marry Isabella of Gloucester.
- The rebel leader Ivanko is captured and executed by the Byzantine general Alexios Palaiologos.
Britain
- November 22 - During a tour of the Midlands, John receives homage from William the Lion, king of Scotland, at Lincoln. William is looking to move into the areas of Northumberland, Cumberland, and Westmoreland. John on the other hand ensures that these areas are controlled by English nobles he can trust.
Levant
- February 17 - Al-Adil I, Ayyubid ruler of Damascus, Jerusalem, and parts of the Jazira takes control of Egypt, and is recognized as sultan of the Ayyubid Empire. During his reign, he promotes trade and good relations with the Crusader States. His son Al-Kamil becomes the effective ruler of Egypt.
Asia
- Temüjin manages to unite about half the feuding Mongol clans under his leadership. He delegates authority based on skill and loyalty, rather than tribal affiliation or family. The main rivals of the Mongol confederation are the Naimans to the west, the Merkits to the north, the Tanguts to the south and the Jin Dynasty to the east.
By topic
Education
- The University of Paris receives its charter, from Philip II. He issues a diploma "for the security of the scholars of Paris", which affirms that students are subject only to ecclesiastical jurisdiction.
Births
- January 19 - Dōgen Zenji, founder of the Sōtō Zen school
- January - Theobald le Botiller, Norman nobleman and knight
- September - Philip I, French prince and nobleman
- October 9 - Isabel Marshal, English countess and regent
- October 22 - Louis IV, landgrave of Thuringia
- unknown dates
- Alix, Breton noblewoman
- Ingerd Jakobsdatter, Danish noblewoman and landowner
- Ulrich von Liechtenstein, German minnesinger and poet
- probable
- * Adam Marsh, English Franciscan scholar and theologian
- * Chen Rong, Chinese painter and politician
- * Jutta of Kulmsee, German noblewoman, hermit and saint
- * Matthew Paris, English Benedictine monk and chronicler
- * Rolandino of Padua, Italian professor, jurist and writer
- * Rudolf von Ems, German nobleman, knight and poet
Deaths
- January 13 - Otto I, German nobleman
- January 14 - Odo of Novara, Italian priest and saint
- January 20 - Odo of Canterbury, English abbot and theologian
- February 6
- * Kajiwara Kagesue, Japanese nobleman
- * Kajiwara Kagetoki, Japanese samurai and spy
- April 8 - Adalbert III, German archbishop
- April 23 - Zhu Xi, Chinese historian and philosopher
- May 25 - Nicholas I, German nobleman
- July 16 - Li Fengniang, Chinese empress
- July 26 - Raymond of Piacenza, Italian pilgrim
- September 19 - Alberic III of Dammartin, French nobleman
- September 17 - Guang Zong, Chinese emperor
- September 24 - Heinrich Walpot, German Grand Master
- October 25 - Conrad of Wittelsbach, German archbishop
- November 16 - Hugh of Avalon, French monk and bishop
- December 12 - Lochlann of Galloway, Scottish nobleman
- December 14 - Han, Chinese empress
- Adachi Morinaga, Japanese Buddhist warrior monk
- Benedicta Ebbesdotter of Hvide, queen of Sweden
- Gilbert Horal, Spanish Grand Master of the Knights Templar
- Inpumon'in no Tayū, Japanese noblewoman and poet
- Joel ben Isaac ha-Levi, German rabbi and Tosafist
- Liu Wansu, Chinese physician of the Jin Dynasty
- Nicholas of Amiens, French theologian and writer
- Nigel de Longchamps, English satirist
- Osbern of Gloucester, English lexicographical writer
- William FitzRalph, English nobleman and knight