Crusader States

The Crusader states, also known as Outremer, were a number of mostly 12th- and 13th-century feudal states created by Western European crusaders in Asia Minor, Greece and the Holy Land, and during the Northern Crusades in the eastern Baltic area. The name also refers to other territorial gains (often small and short-lived) made by medieval Christendom against Muslim and pagan adversaries.

Beginning in the 7th century, Muslim rulers began expanding their territories into Christian Roman/Byzantine lands, conquering Egypt and the Levant, and gradually taking over all of North Africa, much of Southwest Asia, and most of the Iberian Peninsula. The Eastern Romans, or Byzantines, partially recovered lost territory on numerous occasions but over time gradually lost all but Anatolia and parts of Thrace and the Balkans. In the West, the Roman Catholic kingdoms of northern Iberia launched a series of campaigns known as the Reconquista to reconquer the peninsula from the Arabized Berbers known as Moors (who called it al-Andalus). The conquered Iberian principalities are not customarily called Crusader states, except for the Kingdom of Valencia, despite fitting the general criteria.

In 1071, the Byzantine army was defeated by the Muslim Seljuk Turks at the Battle of Manzikert, resulting in the loss of most of Asia Minor. The situation represented a serious existential threat for the Eastern Orthodox Byzantine Empire. The Emperor sent a plea to the Pope in Rome to send military aid with the goal of restoring the formerly Christian territories to Christian rule. The result was a series of western European military campaigns into the eastern Mediterranean, known as the Crusades. Unfortunately for the Byzantines, the crusaders had no allegiance to the Byzantine Emperor and so established their own states in the conquered regions, including the heart of the Byzantine Empire itself.

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