The Graham Phillips Website
Alexander's Death
Perdiccas and Alexander
Some four or five years older than Alexander, Perdiccas was a competent but by no means an outstanding soldier.  However, he did have one of the most varied careers of any of Alexander’s officers.  He commanded an infantry unit until the death of Darius, he was a royal adjutant during the war in Bactria and he became a senior cavalry officer during the Indian campaign.
Perdiccas was clearly a brave soldier, but he lacked any real aptitude for senior command in battle and his appointment, although expedient, was almost certainly temporary.  By June 323 BC, Alexander was preparing for a new campaign in Arabia and it is likely that Perdiccas would soon be replaced.  No one else in the high command appears to have had much enthusiasm for another major war, and if Alexander were to die the chances were the plan would die with him – as indeed it did.  Perdiccas was well aware of this, giving him a prime motive for killing Alexander.
When Alexander died, Perdiccas started a civil war by claiming that the king had made him his successor on his death bed. (From The Death of Alexander by the seventeenth-century artist Karl Theodor von Piloty)
In October 324 BC, Alexander’s deputy Hephaestion fell ill and died.  Hephaestion’s death unexpectedly left Perdiccas as the highest ranking officer at Alexander’s court and he was not only appointed commander of the cavalry but took over the function of vizier – the equivalent of prime minister.  Against all the odds, a common, average soldier had found himself second-in-command of the largest empire the world had ever known.