Antigonus I Monophthalmus vs Duke Wen of Jin

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.

Duke Wen of Jin (then Prince Chong'er) was forced into exile for 19 years after a political purge in Jin. He traveled through several states, gaining experience and allies, before returning to claim the throne of Jin in 636 BCE.

Upon returning to power, Duke Wen implemented administrative and military reforms in Jin. He reorganized the army into three divisions, promoted talented officials regardless of birth, and established a legal code, strengthening Jin's governance.

Duke Wen of Jin defeated the state of Chu at the Battle of Chengpu, the largest battle of the Spring and Autumn period. The victory established Jin as the dominant power and Duke Wen as the hegemon of the Chinese states.

After the Battle of Chengpu, Duke Wen convened a major alliance of states at Jiantu, where he was formally recognized as hegemon. He also received a mandate from the Zhou king to lead military campaigns, solidifying his authority.