Seleucus I Nicator

Seleucus I Nicator, who had served as one of Alexander’s top generals, took leadership of the elite guard after Alexander’s death. Seleucus initially supported Perdiccas, one of Alexander’s generals who became regent over the empire after Alexander’s death. But Seleucus later conspired against Perdiccas and assassinated him ca. 321 bc, inheriting Babylon.

After decades of warring among the Diadochi, Seleucus established an empire encompassing Syria, Mesopotamia, and parts of Asia Minor. He built many new cities, including his capital Seleucia on the west bank of the Tigris River. In 281 bc, Seleucus campaigned westward, aiming for Macedon and Thrace, but Ptolemy Keraunos, a member of the Greek family who ruled over Egypt, murdered Seleucus before the he could gain control of those areas. After Seleucus’ death, his son Antiochus I Soter ascended to the throne and continued the dynastic line.