Spain has been invaded and inhabited by many different peoples. The peninsula was originally settled by groups from North Africa and western Europe, including the Iberians, Celts, and Basques. Throughout antiquity it was a constant point of attraction for the civilizations of the eastern Mediterranean. From c. 1100 bce the Phoenicians, the Greeks, and the Carthaginians began to establish settlements and trading posts, especially on the eastern and southern coasts. These outsiders found a mosaic of peoples, collectively known as the Iberians, who did not have a single culture or even share a single language. A kingdom called Tartessus, which flourished between 800 and 550 bce, ruled much of the valley of the Guadalquivir. Elsewhere political organization was less sophisticated, consisting of a number of city-states in the coastal regions and of clans in the interior and the northwest.