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December - A peace treaty ends the Third War of the Diadochi. Ptolemy and Lysimachus are confirmed as satraps of Egypt and Thrace, respectively, and Antigonus and Cassander are confirmed as commanders of the army in Asia and Europe. Seleucus is left to fend for himself against Antigonus, and it is agreed by all parties that the young king Alexander IV, son of Alexander the Great, will become king of the whole empire when he comes of age in 305 BC. Soon after, Cassander has the boy-king and his mother, Roxane, murdered.