The Romans became the most powerful state in the eastern Mediterranean after wars with Macedonia, and the Mithridatic Wars with Kingdom of Pontus. The Hellenistic period and the Roman Republic ended when, after Julius Caesar was assassinated, the Romans fought a long civil war. At the end of these wars, Augustus overcame his Roman enemies and the Ptolemaic dynasty, who controlled the kingdom of Egypt. Augustus became the first Roman emperor and Roman civilization controlled all the lands around the Mediterranean Sea.