The historic French region of Provence, located in the southeast corner of France between the Alps, the Mediterranean, the Rhone River and the upper reaches of the Durance River, was inhabited by Ligures since Neolithic times; by the Celtic since about 900 BC, and by Greek colonists since about 600 BC. It was conquered by Rome at the end of the 2nd century BC. From 879 until 1486, it was a semi-independent state ruled by the Counts of Provence. In 1481, the title passed to the Louis XI of France. and in 1486 Provence was legally incorporated into France. Provence has been a part of France for over 400 years, but the people of Provence, particularly in the interior, have kept a cultural identity that persists to this day.