Complex sentence: In 1939 Tripolitania was administratively united to the metropolitan Italy, as part of the Greater Italia, but in 1943 the region was invaded and occupied by the Allies: this was the end of the Italian colonial presence.
Split into simpler sentences: In 1939 Tripolitania was administratively united to the metropolitan Italy, as part of the Greater Italia. In 1943 the region was invaded and occupied by the Allies: this was the end of the Italian colonial presence.