The Italian peninsula has been inhabited since prehistoric times. The earliest known settlers were the Italic peoples, who arrived in the area in the 2nd millennium BC. The Italic peoples included the Latins, Umbrians, Samnites, and Oscans. They were followed by the Greeks, who began colonizing the southern part of the peninsula in the 8th century BC. The Greeks established several colonies in southern Italy, including Naples, Syracuse, and Crotone. In the 6th century BC, the Etruscans, a people of unknown origin, emerged in central Italy. The Etruscans were a powerful civilization and their culture had a major influence on the development of Roman civilization. In the 4th century BC, the Celts, a group of people from central Europe, began to migrate into northern Italy. The Celts were eventually conquered by the Romans, who emerged as the dominant power in the peninsula by the end of the 3rd century BC.