In the autumn of 319, Antipater died, the regent of the brother of Alexander the Great and his baby son Alexander. A year before, he had divided Alexander's empire: Ptolemy was recognized as the ruler of a virtually independent Egypt, Antigonus Monophthalmus was made supreme commander of the Macedonian forces in Asia, and Antipater was sole ruler of Macedonia proper. His death led to great changes among the Diadochi.
The historian Diodorus of Sicily describes the events (World History, 18.48.4-50.5). The translation was made by M.M. Austin.
The death of Antipater
[18.48.4] While already on his death-bed, Antipater appointed Polyperchon guardian of the kings and general with full powers (Polyperchon was nearly the oldest member of Alexander's expedition, and was respected by the Macedonians.) His son Cassander he appointed "chiliarch" and second in authority.
[18.48.5] The office and rank of chiliarch was first raised to fame and repute by the Persian kings, and afterwards under Alexander it achieved great power and prestige when he became an admirer of Persian customs. That is why Antipater, imitating the precedent, appointed his son Cassander chiliarch in spite of his youth.
[18.49.1] Cassander, however, was dissatisfied with the arrangement and incensed at the idea that his father's authority should pass to someone who was not related by blood, particularly since Antipater had a son capable of handling affairs who had already given sufficient proof of his merits and bravery.
[18.49.2] At first he went into the country with his friends, where he had ample opportunity and leisure to converse with them on the subject of supreme command. Then he would take each one of them aside in private and urge him to assist in securing his dominion; by great promises he made them all willing allies in his enterprise.
[18.49.3] He also sent messengers in secret to Ptolemy, to renew his friendship with him and invite him to be his ally and send with all haste a navy from Phoenicianote[On hearing the news of Antipater's death, Ptolemy had launched a naval campaign to conquer Phoenicia.] to the Hellespont. Similarly he sent messengers to the other leading men and the Greek cities to urge them to join his side. But he also organized a hunt for many days to dispel any suspicion that he was about to revolt.
[18.49.4] Polyperchon, on his side, assumed the guardianship of the kings and held a meeting of his council with his friends. With their approval he summoned Olympias, inviting her to assume the care of Alexander's son (who was still a child) and to take up residence in Macedonia with royal authority; Olympias had previously fled to Epirus because of her disagreement with Antipater. Such was the state of affairs in Macedonia.
[18.50.1] In Asia, as the news of Antipater's death was noised about, revolutionary stirrings began to be felt, as those in positions of authority sought to work for their own ends. Chief among these was Antigonus. He had previously defeated Eumenes in Cappadocia and taken over his army, and he had overcome Alcetas and Attalus in Pisidia and also taken over their armies. In addition he had been chosen by Antipater general of Asia with full powers, and appointed commander of a large army. All this filled him with self-importance and pride.
[18.50.2] He was hoping to achieve supreme power and resolved to ignore the kings and their guardians. He reckoned that his superior army would make him master of the treasures in Asia, since there was no one in a position to oppose him.
[18.50.3] He had at the time 60,000 infantry, 10,000 cavalry and 30 elephants; apart from these he hoped to procure if necessary other armies, since Asia was capable of providing an inexhaustible source of pay for the mercenaries he recruited.
[18.50.4] With all this in mind he summoned Hieronymus the historian, a friend and fellow-citizen of Eumenes of Cardia who had taken refuge with him at the fort called Nora. He attempted to win him over with lavish gifts and sent him on an embassy to Eumenes: let Eumenes forget about the battle they had fought in Cappadocia, become his friend and ally, receive far more gifts than he had ever done before and a larger satrapy, and in general be ranked the first of his friends and participate in his whole enterprise.
[18.50.5] Antigonus then immediately called a council of his friends, communicated to them his ambitions for supreme power, and assigned satrapies to some of his most prominent followers and military commands to others. He filled them all with great hopes and made them enthusiastic for his own plans. For it was his intention to overrun Asia, expel the existing satraps and organize the appointments in favor of his friends.