Antigonus I (Antigonus the One-Eyed or Antigonus Cyclops) (ăntig´ənəs sī´klo˘ps), 382?–301 BC, general of Alexander the Great and ruler in Asia. He was made (333 BC) governor of Phrygia, and after the death of Alexander he was advanced by the friendship of Antipater, who with Ptolemy I and Craterus, supported Antigonus in 321 against Perdiccas and Eumenes. In the wars of the Diadochi, Antigonus was the leading figure because he seems to have had the best chance to re-create Alexander's empire. He had control of Asia Minor, Syria, and Mesopotamia at the time (316) when Eumenes was murdered. His great power, however, ultimately caused Lysimachus, Seleucus I, and Ptolemy I to unite against him. Antigonus' son, Demetrius Poliorcretes (later Demetrius I of Macedon), was an able agent in the bid to build the empire by invading Greece; Antigonus defeated (306) Ptolemy, but both Antigonus and Ptolemy were conquered at the battle at Ipsus (301). Antigonus was killed.