Long before any Roman settlements, Greek navigators settled in what would become Provence. The Phoceans founded important cities such as Massalia (Marseille) and Nikaia (Nice), bringing them into conflict with the neighboring Celts and Ligurians. Some Phocean great navigators, such as Pytheas, were born in Marseille. The Celts themselves often fought with Aquitanians and Germans, and a Gaulish war band led by Brennus invaded Rome c. 393 or 388 BC following the Battle of the Allia.