13th century

The 13th century consists of the years 1201-1300 AD.
==Events==
===General===
* The Roman Catholic Church begins to codify canon law.
* 1250 to 1289. Various battles between the Guelphs and Ghibellines, factions supporting, respectively, the Papacy and the Holy Roman Empire in central and northern Italy during the 12th and 13th centuries. The struggle for power between the Papacy and the Holy Roman Empire had actually arisen with the Investiture Conflict of the 11th century.
* 1291. The Kingdom of Jerusalem, established by the First Crusade but conquered at various times by Christian Crusades and Muslim Mamluks, falls to Muslims for the final time. Jerusalem remains under Muslim control until the collapse of the Ottoman Empire in 1924.
* 1299. Rise of the Ottoman Empire.
===Ecumenical councils===
* 1215. Fourth Lateran Council deals with transubstantiation, papal primacy and conduct of clergy. The council required Jews and Muslims should wear a special dress to enable them to be distinguished from Christians. 
* 1245. First Council of Lyons mandates the red hat for cardinals, and a levy for the Holy Land. 
* 1245. Second Council of Lyons attempts reunion with the Eastern churches. The council also approves Franciscan and Dominican Orders, calls for a tithe to support the crusades, and establishes conclave procedure.
===Crusades===
* 1201-1204. Pope Innocent III calls the Fourth Crusade, originally designed to conquer Jerusalem through an invasion of Egypt. Instead, in 1204, the crusaders invaded and conquered the Eastern Orthodox city of Constantinople, capital of the Byzantine Empire.
* 1209-1229. Pope Innocent III cals the Albigensian or Cathar Crusade, to eliminate the Cathars of Languedoc, France, which the Roman Catholic hierarchy considered apostasy.
* 1212. Children's Crusade.
* 1217-1221. Pope Innocent III calls the Fifth Crusade, again attempting to conquer Egypt and the Holy Land.
* 1228. Despite excommunication by Pope Gregory IX, Holy RomanEmperor Frederick II launched the Sixth Crusade to reconquer Jerusalem via Syria.
* 1248-1254. King Louis IX of France launches the Seventh Crusade to again reconquer Jerusalem. Hr receives little support, as the pope and Holy Roman Emperor are fighting over invesiture (see above.)
* 1270. King Louis IX of France launches the Eighth Crusade to conquer Jerusalem and Syria.
* 1271. Prince Edward of England (later King Edward I launches the Ninth Crusade to support Louis IX. This is the last of the crusades in the Holy Land.
* 1284-1285. Pope Martin IV declares the Aragonese Crusade against the King of Aragón (modern Spain), Peter the Great, The Pope declared that Peter's grandfather had surrendered the Kingdom of Sicily (then under Aragonese control) as a fief to the Holy See.
==Births and deaths==
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Category:Centuries