Complex sentence: In the 4th century BC Thessaly became dependent on Macedon and many served as vassals, while in 148 BC the Romans formally incorporated Thessaly into the province of Macedonia, though in 300 AD Thessaly was made a separate province with its capital at Larissa.
Split into simpler sentences: In the 4th century BC Thessaly became dependent on Macedon and many served as vassals. In 148 BC the Romans formally incorporated Thessaly into the province of Macedonia, though in 300 AD Thessaly was made a separate province with its capital at Larissa.