Lysimăchus in Harpers Dictionary of Classical Antiquities
（Λυσίμαχος). One of Alexander's generals, who obtained Thrace in the division of the provinces after Alexander's death (B.C. 323), and assumed the title of king in B.C. 306. He joined the other generals of Alexander in opposing Antigonus, and it was he and Seleucus who gained the decisive victory at Ipsus over Antigonus, in which the latter fell (B.C. 301). In B.C. 291 Lysimachus was taken prisoner by Dromichaetes, king of the Getae, whose country he had invaded, but he was restored to liberty by the latter. In B.C. 287 Lysimachus and Pyrrhus expelled Demetrius from Macedonia. Pyrrhus, for a time, obtained possession of the Macedonian throne; but in the following year he was driven out of the country by Lysimachus, who now became king of Macedonia. Towards the end of his reign the aged Lysimachus put to death his son Agathocles, at the instigation of his wife, Arsinoe, daughter of Ptolemy Soter. This bloody deed alienated the minds of his subjects, and Seleucus invaded the dominions of Lysimachus. The two monarchs met in the plain of Corus (Corupedion), and Lysimachus fell in the battle that ensued, B.C. 281, in his eightieth year.
Lysimachus in Wikipedia
Lysimachus (Greek: Λυσίμαχος, Lysimachos; 360 BCE - 281 BCE) was a Macedonian officer and diadochus (i.e. "successor") of Alexander the Great, who became a basileus ("king") in 306 BCE, ruling Thrace, Asia Minor and Macedonia.
Lysimachus was born in 362/361 BC, the son of the Thessalian Agathocles from Crannon. He was granted citizenship in Macedon and was educated at the court in Pella. He was probably appointed Somatophylax during the reign of Philip II. During Alexander's Persian campaigns, he was one of his immediate bodyguards. In 324 BCE, in Susa, he was crowned in recognition for his actions in India. After Alexanderís death in 323 BCE, he was appointed to the government of Thrace as strategos.
In 315 BCE, he joined Cassander, Ptolemy and Seleucus against Antigonus, who, however, diverted his attention by stirring up Thracian and Scythian tribes against him. In 309 BCE, he founded Lysimachia in a commanding situation on the neck connecting the Chersonese with the mainland. He followed the example of Antigonus in taking the title of king.
In 306 or 305, he assumed the title of "King", which he held until his death at Corupedium in 282/1.
In 302, when the second affiance between Cassander, Ptolemy and Seleucus was made, Lysimachus, reinforced by troops from Cassander, entered Asia Minor, where he met with little resistance. On the approach of Antigonus he retired into winter quarters near Heraclea, marrying its widowed queen Amastris, a Persian princess. Seleucus joined him in 301 BCE, and at the battle of Ipsus Antigonus was defeated and slain. His dominions were divided among the victors. Lysimachus share was Lydia, Ionia, Phrygia and the north coast of Asia Minor.
Feeling that Seleucus was becoming dangerously great, Lysimachus now allied himself with Ptolemy, marrying his daughter Arsinoe II of Egypt. Amastris, who had divorced herself from him, returned to Heraclea. When Antigonusís son Demetrius I of Macedon renewed hostilities (297 BCE), during his absence in Greece, Lysimachus seized his towns in Asia Minor, but in 294 BCE concluded a peace whereby Demetrius was recognized as ruler of Macedonia. He tried to carry his power beyond the Danube, but was defeated and taken prisoner by the Getae king Dromichaetes (Dromihete), who, however, set him free on amicable terms. Demetrius subsequently threatened Thrace, but had to retire due to a sudden uprising in Boeotia, and an attack from the king Pyrrhus of Epirus.
In 288 BCE, Lysimachus and Pyrrhus in turn invaded Macedonia, and drove Demetrius out of the country. Lysimachus left Pyrrhus in possession of Macedonia with the title of king for around seven months before Lysimachus invaded. For a short while the two ruled jointly but in 285 BCE Lysimachus expelled Pyrrhus.
Domestic troubles embittered the last years of Lysimachusís life. Amastris had been murdered by her two sons; Lysimachus treacherously put them to death. On his return Arsinoe asked the gift of Heraclea, and he granted her request, though he had promised to free the city. In 284 BCE Arsinoe, desirous of gaining the succession for her sons in preference to Agathocles (the eldest son of Lysimachus), intrigued against him with the help of her brother Ptolemy Keraunos; they accused him of conspiring with Seleucus to seize the throne, and he was put to death.
This atrocious deed of Lysimachus aroused great indignation. Many of the cities of Asia revolted, and his most trusted friends deserted him. The widow of Agathocles fled to Seleucus, who at once invaded the territory of Lysimachus in Asia. In 281 BCE, Lysimachus crossed the Hellespont into Lydia, and at the decisive Battle of Corupedium was killed. After some days his body was found on the field, protected from birds of prey by his faithful dog. Lysimachus's body was given over to his son Alexander, by whom it was interred at Lysymachia.