Complex sentence: From their earliest days, both the Greeks and Phoenicians had been attracted to the large island, establishing a large number of colonies and trading posts along its coasll battles had been fought between these settlements for centuries.
Split into simpler sentences: From their earliest days, both the Greeks and Phoenicians had been attracted to the large island, establishing a large number of colonies and trading posts along its coasts. Small battles had been fought between these settlements for centuries.