Eumenes initially served as Alexander's royal secretary, distinguishing himself in both administrative and military roles. After Alexander's death, he became a strong proponent of maintaining the unity of the empire and a loyal supporter of the Argead dynasty.
He received Cappadocia and Paphlagonia in the Partition of Babylon and was a key ally of Perdiccas. After Perdiccas's death, Eumenes continued to fight against the anti-Argead faction, primarily led by Antigonus I Monophthalmus.
Despite his military skill, Eumenes faced immense challenges due to his Greek origin among Macedonian generals. He was ultimately betrayed by his own troops and handed over to Antigonus, who had him executed in 316 BCE, effectively eliminating the last major defender of Alexander's unified empire.