The Diadochi (literally, ‘successors’) were the military commanders and administrators who ruled the cities and regions conquered by Alexander III ‘the Great’ of Macedon, who had no designated successors. Following his death in 323 BCE, a triumvirate emerged that comprised: Perdiccas, nominated ‘Regent of the Empire’; Craterus, the military commander in Persia; and Antipater the regent of Macedon and Greece. Decades of conflict ensued as Alexander’s generals vied for power. The most stable legacy was Egypt, and some neighbouring parts of the Middle East, where Ptolemy I Soter held sway, establishing a secure dynasty. Elsewhere the situation was much more confused. Perdiccas had raised the suspicions of his fellow regional governors, Ptolemy in Egypt, Antigonus in Phrygia, Craterus in Babylon and Antipater in Macedonia. This suspicion culminated in an out and out conflict between Perdiccas and Ptolemy, and mutinous officers murdered Perdiccas. At this stage Seleucus was the governor in Babylon, and Lysimachus, one of Alexander’s Macedonian bodyguards, now ruled in Thrace. When Antigonus, ruler of Phrygia, began to nurse overweaning ambitions a coalition of Cassander (son of Antipater), Ptolemy and Lysimachus took up arms against him from 320–311. Eventually, Seleucus joined the alliance against Antigonus, who was defeated at the Battle of Ipsus in 301. Further disputes led to a confrontation between Lysimachus and Seleucus, in which Seleucus was the victor. Three main kingdoms had now emerged from the chaotic disintegration of Alexander’s empire: Ptolemy ruled Egypt, Seleucus ruled in Syria and the remnants of the Persian empire, and Antigonus (succeeded by his son Demetrius) ruled in Macedonia, Thrace and northern Asia Minor.
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