Antigonus I Monophthalmus (meaning 'the One-Eyed') was a Macedonian nobleman, general, and satrap under Alexander the Great.
During the Wars of the Diadochi, he initially tried to maintain the unity of Alexander's empire and became the most powerful among the successors, controlling much of Asia Minor and Syria.
His ambition to reunite the empire under his rule led to conflict with the other Diadochi. He was eventually defeated and killed at the Battle of Ipsus in 301 BC, and his territories were divided among the victors.
Despite his defeat, his son Demetrius I Poliocretes would later establish the Antigonid dynasty, which ruled Macedon for over a century.