Editing Eighth Crusade (section)

===Conflict over Saint Sabas===

In addition to the Muslim wars between the [[Mamluk Sultanate|Mamluks]] and [[Ayyubid dynasty|Ayyubids]], and the [[Mongol invasions of the Levant]], the Outremer states had to contend with the various Italian merchants engaged in the [[War of Saint Sabas]]. The three rival Italian cities of [[Genoa]], [[Venice]] and [[Pisa]] maintained a presence in every Outremer seaport and from these, dominated Mediterranean trade. This commerce was equally beneficial to the Muslim emirs and both sides showed a willingness to sign treaties partially based on the fear of interrupting these sources of profit. Trouble between Pisa and Genoa had long been brewing and in 1250, a Genoese merchant was murdered by a Venetian, resulting in street fighting in Acre. When Louis finally returned home to Europe in 1254, trouble again broke out. In 1256, the commercial rivalry between the Venetian and Genoese merchant colonies erupted over possession of the monastery of Saint Sabas in Acre. The Genoese, assisted by the Pisan merchants, attacked the Venetian quarter and burned their ships, but the Venetians drove them out.{{sfn|Marshall|1994|pp=217–231|loc=Sieges}}

The Venetians were then expelled from Tyre by [[Philip of Montfort, Lord of Tyre|Philip of Montfort]]. The Venetians were supported by [[John of Arsuf]], [[John of Ibelin (jurist)|John of Jaffa]], [[John II of Beirut]], the [[Knights Templar]], the [[Teutonic Order|Teutonic Knights]] and the Pisans. The [[Knights Hospitaller]] supported the Genoese. In 1257, the Venetians conquered the monastery and destroyed its fortifications, although they were unable to completely expel the Genoese. The Genoese quarter was blockaded, who were then resupplied by the Hospitallers, whose complex was nearby. Philip of Montfort also sent food from Tyre. In August 1257, John of Arsuf tried to end the war by granting commercial rights in Acre to the [[Republic of Ancona]], an Italian ally of Genoa, but aside from Philip of Montfort and the Hospitallers, the rest of the nobles continued to support Venice.{{sfn|Runciman|1969|pp=568–570|loc=The War of Saint Sabas}}