Military history of the Crusader states
The Seljuk–Crusader War began when the First Crusade wrested territory from the Seljuk Turks during the Siege of Nicaea in 1097 and lasted until 1128 when Zengi became atabeg of Aleppo. At the latter date, the chief threat to the Crusaders from the east and north became the Zengids. The conflict was generally fought between European Crusaders and the Seljuk Turks and their vassals. The Muslim Syrian emirates occasionally allied themselves with the Christians against rival states.
Deus vult
The battle cry of the First Crusade is reported in the "Gesta Francorum", written by an anonymous author associated with Bohemond I of Antioch shortly after the successful campaign, in 1100 or 1101. According to this description, as the Princes Crusade gathered in Amalfi in the late summer of 1096, there assembled a large number of crusaders, armed and bearing the sign of the cross on their right shoulders or on their backs, crying in unison ""Deus le volt, Deus le volt, Deus le volt"". The "Historia belli sacri", written somewhat later, c. 1131, also cites the battle cry.