and the Byzantine Empire.

In 1137, 1167, and 1174 it was strong enough to push back the forces of the Holy Roman Empire. Anconitan ships took part in the Crusades, and their navigators included Cyriac of Ancona. In the struggle between the Popes and the Holy Roman Emperors that troubled Northern and central Italy from the 12th century onwards, Ancona sided with the Popes (Guelphs).