Some Greeks had emigrated from the mainland eastward across the Aegean Sea to settle in Ionia as early as the ninth century B.C. Starting around 750 B.C., however, Greeks began to settle even farther outside the Greek homeland. Within two hundred years, Greek colonies were established in areas that are today southern France, Spain, Sicily and southern Italy, and along North Africa and the coast of the Black Sea. Eventually the Greek world had perhaps as many as 1,500 different city-states. A scarcity of arable land certainly gave momentum to emigration from Greece, but the revival of international trade in the Mediterranean in this era perhaps provided the original stimulus for Greeks to leave their homeland, whose economy was still struggling. Some Greeks with commercial interests took up residence in foreign settlements, such as those founded in Spain in this period by the Phoenicians from Palestine. The Phoenicians were active in building commercially-motivated settlements throughout the western Mediterranean. Within a century of its foundation sometime before 750 B.C., for example, the Phoenician settlement on the site of modern Cadiz in Spain had become a city thriving on economic and cultural interaction with the indigenous Iberian population.