 During the late 11th and the 12th centuries, the city of Dyrrhachium and its province were of great importance to the Byzantine Empire.The city was the "key of Albania" and the main point of entry for trade but also for invaders from Italy, and was ideally placed to control the actions of the Slavic rulers of the western Balkans.Thus the "doux" of Dyrrhachium became the senior-most Byzantine authority throughout the western Balkan provinces.