Answer
Allies: Alexios I, the Byzantine emperor, formed an alliance with the Crusaders. He sought their assistance in regaining control of territories lost to the Seljuk Turks. In exchange, he promised them supplies, guidance, and safe passage through his empire. This alliance proved mutually beneficial, as the Crusaders helped Alexios recover some of his lost lands, while the Byzantines provided essential support to the Crusaders' campaign.