War of the Lombards

Also known as Imperial–Ibelin war

The fifteen-year struggle between supporters of the Holy Roman Emperor Frederick II and the local baronial party led by the Ibelins — out of which emerged the most fully articulated feudal constitution of the medieval Latin East.

Frederick II claimed the kingdom of Jerusalem in right of his wife Isabella II and, after her death, as regent for their son Conrad II. He attempted to impose centralised imperial rule on the realm through a series of bailiffs (the 'Lombards' of contemporary chronicles, named for their north-Italian origins), which the local nobility — led by the powerful Ibelin family — viewed as a violation of their traditional feudal rights and the customary law of the Haute Cour.

The conflict ranged across Cyprus and the Levantine mainland for fifteen years. Major engagements included the imperial garrison's holding of Tyre, the Ibelin victory at the Battle of Agridi (1232) on Cyprus, and the long sieges of the Hohenstaufen-held castles of Saint Hilarion, Buffavento and Kantara — four-year struggles that ended with the imperial party expelled from the island.

The Ibelins and their allies eventually drove out the imperial representatives from the mainland as well. From 1243 until the fall of the kingdom in 1291 the throne remained effectively vacant or held by absentee Hohenstaufen heirs, and real authority lay with the Haute Cour and the great baronial families. The legal treatises of John of Ibelin, Philip of Novara, and the Livre au roi were composed in the wake of this conflict and codify the constitutional theory the war produced.

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