Antigonus I Monophthalmus vs Euthydemus I

Antigonus I defeated Eumenes, a former general of Alexander, at Gabiene in Persia. This victory eliminated a major rival and gave Antigonus control over the eastern satrapies, making him the most powerful of the Diadochi at that time.

Antigonus I besieged and captured the city of Tyre from Ptolemy I's forces. The siege demonstrated his military capabilities and expanded his control over Phoenicia and Syria, strengthening his position in the Diadochi conflicts.

Antigonus I declared himself king of Asia, claiming authority over the entire former empire of Alexander. This act prompted other Diadochi to also assume royal titles, formalizing the breakup of Alexander's empire into separate Hellenistic kingdoms.

Antigonus I Monophthalmus commanded his army against the allied forces of Seleucus, Lysimachus, and Cassander at Ipsus. He was defeated and killed in battle, ending his ambition to reunite Alexander's empire. His death solidified the division of the empire among the other Diadochi.

Euthydemus I, a Magnesian Greek, overthrew and killed Diodotus II, seizing the throne of the Greco-Bactrian Kingdom. This began the Euthydemid dynasty.

Euthydemus I was besieged in Bactra by the Seleucid king Antiochus III for two years. The siege ended with a negotiated peace that recognized Euthydemus's rule.

Euthydemus I negotiated a peace treaty with Antiochus III, recognizing Seleucid suzerainty in name but securing Greco-Bactrian independence. The treaty included a marriage alliance between the two dynasties.

Euthydemus I expanded the Greco-Bactrian Kingdom eastward into Sogdiana and possibly Ferghana. This extended Hellenistic influence deeper into Central Asia.