Complex sentence: A large number of Italian colonists moved to Tripolitania in the late 1930s: these settlers went primarily to the area of Sahel al-Jefara in Tripolitania and in the capital Tripoli.
Split into simpler sentences: A large number of Italian colonists moved to Tripolitania in the late 1930s. These settlers went primarily to the area of Sahel al-Jefara, in Tripolitania, and in the capital Tripoli.