An important medieval Russian city, capital of the Ukraine, on the eastern bank of the Dnepr River. In the 10th century, small hamlets were built with sunken-floored workshops, merchant houses, and artisans' dwellings. A fortified town with churches and palaces grew through the 11th centuries. Kiev had developed into an important political and trade center on the route from the Baltic to Byzantium. The influence of Byzantium is apparent on local monumental architecture of the 11th-14th centuries. It was sacked by the Mongols in the 13th century.