Battle of Ipsus

The Battle of Ipsus was fought between some of the Diadochi in 301 BC near the town of Ipsus in Phrygia. Antigonus I Monophthalmus, ruler of Phrygia, and his son Demetrius I of Macedon were pitted against the coalition of three other sucessors of Alexander: Cassander, ruler of Macedon; Lysimachus, ruler of Thrace; and Seleucus I Nicator, ruler of Babylonia and Persia. Only one of these leaders, Lysimachus, had actually been one of Alexander's somatophylakes, that is "body guards."

Diodorus Siculus is the principal source for the history of the Diadochi, in his 'Library of history' . Diodorus is often derided by modern historians for his style and inaccuracies, but he preserves many details of the ancient period found nowhere else. Diodorus worked primarily by epitomizing the works of other historians, omitting many details where they did not suit his purpose, which was to illustrate moral lessons from history. However, since Diodorus provides the only continuous narrative for the history of the Diadochi, we have no alternative but to rely on his account. Unfortunately, from book XXI onwards , including the actual Battle of Ipsus, the Bibliotheca only exists in fragments. Nevertheless, Diodorus provides extensive details of the Fourth War of the Diadochi leading up to Ipsus. It is generally thought that Diodorus's source for much of this period was the now-lost history of the Diadochi written by Hieronymus of Cardia. Hieronymus was a friend of Eumenes, and later became a member of the Antigonid court; he was therefore very much familiar and contemporary with the events he described, and possibly a direct eyewitness to some.

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