Editing Seleucus I Nicator (section)

==Senior officer under Perdiccas (323–321 BC)==
[[File:Ptolemy I Soter Louvre Ma849.jpg|thumb|left|upright|[[Ptolemy I Soter]], an officer under Alexander the Great, was nominated as the [[satrap]] of Egypt. Ptolemy made [[Ptolemaic Egypt]] independent and proclaimed himself [[Basileus]] and [[Pharaoh]] in 305 BC.]]
{{Main|Diadochi}}

Alexander the Great died without a successor in Babylon on June 10, 323 BC. His general [[Perdiccas]] became the regent of all of Alexander's empire, while Alexander's physically and mentally disabled half-brother Arrhidaeus was chosen as the next king under the name [[Philip III of Macedon]]. Alexander's unborn child ([[Alexander IV of Macedon|Alexander IV]]) was also named his father's successor. In the "[[Partition of Babylon]]" however, Perdiccas effectively divided the enormous Macedonian dominion among Alexander's generals. Seleucus was chosen to command the [[Companion cavalry]] (''hetairoi'') and appointed first or court [[chiliarch]], which made him the senior officer in the Royal Army after the regent and commander-in-chief Perdiccas. Several other powerful men supported Perdiccas, including [[Ptolemy I Soter|Ptolemy]], [[Lysimachus]], [[Peithon]] and [[Eumenes]]. Perdiccas' power depended on his ability to hold Alexander's enormous empire together, and on whether he could force the [[satrap]]s to obey him.<ref name="Heckel p. 256"/>

War soon broke out between Perdiccas and the other [[Diadochi]]. To cement his position, Perdiccas tried to marry Alexander's sister [[Cleopatra of Macedon|Cleopatra]]. The [[First War of the Diadochi]] began when Perdiccas sent Alexander's corpse to Macedonia for burial. Ptolemy however captured the body and took it to [[Alexandria]]. Perdiccas and his troops followed him to Egypt, whereupon Ptolemy conspired with the satrap of Media, [[Peithon]], and the commander of the ''[[Argyraspides]]'', [[Antigenes (general)|Antigenes]], both serving as officers under Perdiccas, and assassinated him. [[Cornelius Nepos]] mentions that Seleucus also took part in this conspiracy, but this is not certain.<ref name="G20">Grainger 1990, pp. 20–24</ref>