The Wars of the Diadochi (Ancient Greek: Πόλεμοι τῶν Διαδόχων, romanized: Pólemoi tōn Diadóchōn, lit. 'War of the Crown Princes') or Wars of Alexander's Successors of 322–272 BC were a series of conflicts fought between the generals of Alexander the Great, known as the Diadochi, over who would rule his empire following his death. The fighting started almost immediately after his death in 323 BC. The crucial battle of Ipsus fought in 301 BC, established Ptolemies and Seleucids as the two major dynasties of the Hellenistic world. The battle of Corupedium in 281 BC, left Seleucus I as the only living successor among the original Diadochi. However, the struggle over Macedon and hegemony over Greece was concluded in favour of the Antigonids only in 272 BC with the death of Pyrrhus of Epirus.
Background
Alexander the Great died on June 10, 323 BC, leaving behind an empire that stretched from Macedon and the rest of Greece in Europe to the Indus valley in South Asia. The empire had no clear successor, with the Argead family at this point consisting of Alexander's mentally disabled half-brother Arrhidaeus, his unborn son Alexander IV, his reputed illegitimate son Heracles, his mother Olympias, his sister Cleopatra, and his half-sisters Thessalonike and Cynane.
Alexander's death was the catalyst for the disagreements that ensued between his former generals resulting in a succession crisis. Two main factions formed after the death of Alexander. The first of these was led by Meleager, who supported the candidacy of Alexander's half-brother, Arrhidaeus. The second was led by Perdiccas, the leading cavalry commander, who believed it would be best to wait until the birth of Alexander's unborn child by Roxana. Both parties agreed to a compromise, wherein Arrhidaeus would become king as Philip III and rule jointly with Roxana's child, providing it was a male heir. Perdiccas was designated as regent of the empire, with Meleager acting as his lieutenant. However, soon after, Perdiccas had Meleager and the other leaders who had opposed him murdered, and he assumed full control.
The generals who had supported Perdiccas were rewarded in the partition of Babylon by becoming satraps of the various parts of the empire. Ptolemy received Egypt; Laomedon received Syria and Phoenicia; Philotas took Cilicia; Peithon took Media; Antigonus received Phrygia, Lycia and Pamphylia; Asander received Caria; Menander received Lydia; Lysimachus received Thrace; Leonnatus received Hellespontine Phrygia; and Neoptolemus had Armenia. Macedon and the rest of Greece were to be under the joint rule of Antipater (who had governed them for Alexander) and Craterus, a lieutenant of Alexander. Alexander's secretary, Eumenes of Cardia, was to receive Cappadocia and Paphlagonia.
In the east Perdiccas largely left Alexander's arrangements intact – Taxiles and Porus ruled over their kingdoms in India; Alexander's father-in-law Oxyartes ruled Gandara; Sibyrtius ruled Arachosia and Gedrosia; Stasanor ruled Aria and Drangiana; Philip ruled Bactria and Sogdiana; Phrataphernes ruled Parthia and Hyrcania; Peucestas governed Persis; Tlepolemus had charge over Carmania; Atropates governed northern Media; Archon got Babylonia; and Arcesilas ruled northern Mesopotamia.
Lamian War
The news of Alexander's death inspired a revolt in Greece, known as the Lamian War. Athens and other cities formed a coalition and besieged Antipater in the fortress of Lamia. However, Antipater was relieved by a force sent by Leonnatus, who was killed in battle. The Athenians were defeated at the Battle of Crannon on September 5, 322 BC, by Craterus and his fleet.
At this time, Peithon suppressed a revolt of Greek settlers in the eastern parts of the empire, and Perdiccas and Eumenes subdued Cappadocia.
First War of the Diadochi, 321–319 BC
Perdiccas, who was married to Antipater's daughter, also sought to marry Alexander the Great's sister, Cleopatra. This marriage would have strengthened his political position and provided a basis to become king of Macedonia. In response to this, in 322 BC, the generals Antipater, Craterus and Antigonus all formed a coalition to oppose Perdiccas's growing political influence. Antipater then sent an army under the command of Craterus into Asia Minor. In late 322 or early 321 BC, Ptolemy intercepted Alexander's body on its way to Macedonia, after which he joined the coalition against Perdiccas. An army commanded by Eumenes defeated Craterus at the battle of the Hellespont; however, Perdiccas was soon after assassinated by his own generals, Peithon, Seleucus, and Antigenes, following a failed attempt to cross the Nile.
Ptolemy came to terms with Perdiccas's murderers, making Peithon and Arrhidaeus regents in Perdiccas's place, but soon these came to a new agreement with Antipater at the Treaty of Triparadisus. Antipater was made Regent of the Empire, and the two kings were moved to Macedon. Antigonus was made Strategos of Asia and remained in charge of Phrygia, Lycia, and Pamphylia, to which was added Lycaonia. Ptolemy retained Egypt, Lysimachus retained Thrace, while the three murderers of Perdiccas—Seleucus, Peithon, and Antigenes—were given the provinces of Babylonia, Media, and Susiana respectively. Arrhidaeus, the former regent, received Hellespontine Phrygia. Antigonus was charged with the task of rooting out Perdiccas's former supporter, Eumenes. In effect, Antipater retained for himself control of Europe, while Antigonus, as Strategos of the East, held a similar position in Asia.
Although the First War ended with the death of Perdiccas, his cause lived on. Eumenes was still at large with a victorious army in Asia Minor. So were Alcetas, Attalus, Dokimos and Polemon who had also gathered their armies in Asia Minor. In 319 BC, Antigonus, after receiving reinforcements from Antipater's European army, first campaigned against Eumenes (see: battle of Orkynia), then against the combined forces of Alcetas, Attalus, Dokimos and Polemon (see: battle of Cretopolis), defeating them all.
Second War of the Diadochi, 318–316 BC
Another war soon broke out between the Diadochi. At the start of 318 BC Arrhidaios, the governor of Hellespontine Phrygia, tried to take the city of Cyzicus. Antigonus, as the Strategos of Asia, took this as a challenge to his authority and recalled his army from their winter quarters. He sent an army against Arrhidaios while he himself marched with the main army into Lydia against its governor Cleitus whom he drove out of his province.
Cleitus fled to Macedon and joined Polyperchon, the new Regent of the Empire, who decided to march his army south to force the Greek cities to side with him against Cassander and Antigonus. Cassander, reinforced with troops and a fleet by Antigonus, sailed to Athens and thwarted Polyperchon's efforts to take the city. From Athens Polyperchon marched on Megalopolis which had sided with Cassander and besieged the city. The siege failed and he had to retreat losing a lot of prestige and most of the Greek cities. Eventually Polyperchon retreated to Epirus with the infant King Alexander IV. There he joined forces with Alexander's mother Olympias and was able to re-invade Macedon. King Philip Arrhidaeus, Alexander's half-brother, having defected to Cassander's side at the prompting of his wife, Eurydice, was forced to flee, only to be captured in Amphipolis, resulting in the execution of himself and the forced suicide of his wife, both purportedly at the instigation of Olympias. Cassander rallied once more, and seized Macedon. Olympias was murdered, and Cassander gained control of the infant King and his mother. Eventually, Cassander became the dominant power in the European part of the Empire, ruling over Macedon and large parts of Greece.
Meanwhile, Eumenes, who had gathered a small army in Cappadocia, had entered the coalition of Polyperchon and Olympias. He took his army to the royal treasury at Kyinda in Cilicia where he used its funds to recruit mercenaries. He also secured the loyalty of 6,000 of Alexander's veterans, the Argyraspides (the Silver Shields) and the Hypaspists, who were stationed in Cilicia. In the spring of 317 BC he marched his army to Phoenica and began to raise a naval force on the behalf of Polyperchon. Antigonus had spent the rest of 318 BC consolidating his position and gathering a fleet. He now used this fleet (under the command of Nicanor who had returned from Athens) against Polyperchon's fleet in the Hellespont. In a two-day battle near Byzantium, Nicanor and Antigonus destroyed Polyperchon's fleet. Then, after settling his affairs in western Asia Minor, Antigonus marched against Eumenes at the head of a great army. Eumenes hurried out of Phoenicia and marched his army east to gather support in the eastern provinces. In this he was successful, because most of the eastern satraps joined his cause (when he arrived in Susiana) more than doubling his army. They marched and counter-marched throughout Mesopotamia, Babylonia, Susiana and Media until they faced each other on a plain in the country of the Paraitakene in southern Media. There they fought a great battle, the battle of Paraitakene, which ended inconclusively. The next year (315) they fought another great but inconclusive battle, the battle of Gabiene, during which some of Antigonus's troops plundered the enemy camp. Using this plunder as a bargaining tool, Antigonus bribed the Argyraspides who arrested and handed over Eumenes. Antigonus had Eumenes and a couple of his officers executed. With Eumenes's death, the war in the eastern part of the Empire ended.
Antigonus and Cassander had won the war. Antigonus now controlled Asia Minor and the eastern provinces, Cassander controlled Macedon and large parts of Greece, Lysimachus controlled Thrace, and Ptolemy controlled Egypt, Syria, Cyrene and Cyprus. Their enemies were either dead or seriously reduced in power and influence.
Third War of the Diadochi, 315–311 BC
After Antigonus defeated Eumenes, the eastern dynasts did not want Antigonus to control all of Asia. In 314 BC they demanded that he cede Lycia and Cappadocia to Cassander, Hellespontine Phrygia to Lysimachus, all of Syria to Ptolemy, and Babylonia to Seleucus. Antigonus responded by advising them to be ready for war. In this war Antigonus faced an alliance of Ptolemy (with Seleucus serving him), Lysimachus, and Cassander. At the start of the campaigning season in 314 BC Antigonus invaded Syria and Phoenicia, which were under Ptolemy's control, and besieged Tyre. Cassander and Ptolemy started supporting Asander (satrap of Caria) against Antigonus who ruled the neighboring provinces of Lycia, Lydia and Greater Phrygia. Antigonus then sent Aristodemus with 1,000 talents to the Peloponnese to raise a mercenary army to fight Cassander. Antigonus then allied himself to Polyperchon, who still controlled parts of the Peloponnese, and proclaimed freedom for the Greeks to appeal to the civilians. He also sent his nephew Ptolemaios with an army through Cappadocia to the Hellespont to cut Asander off from Lysimachus and Cassander. Ptolemaios was successful, securing the northwest of Asia Minor for Antigonus, even invading Ionia/Lydia and bottling up Asander in Caria, but he was unable to drive his opponent from his satrapy.
Eventually Antigonus decided to campaign against Asander himself, leaving his oldest son Demetrius to protect Syria and Phoenica against Ptolemy. Ptolemy and Seleucus invaded from Egypt and defeated Demetrius in the Battle of Gaza. After the battle, Seleucus went east and secured control of Babylon (his old satrapy), and then went on to secure the eastern satrapies of Alexander's empire. Antigonus, having defeated Asander, sent his nephews Telesphorus and Polemaios to Greece to fight Cassander, he himself returned to Syria/Phoenica, drove off Ptolemy, and sent Demetrius east to take care of Seleucus. Although Antigonus now concluded a compromise peace with Ptolemy, Lysimachus, and Cassander, he continued the war with Seleucus, attempting to recover control of the eastern reaches of the empire. Although he went east himself in 310 BC, he was unable to defeat Seleucus (he even lost a battle to Seleucus) and had to give up the eastern satrapies.