by Robert Hamilton
In beginning to answer the question, why did Alexander set out to invade Persian territory? We must firstly accept, that we have veracity in the actions taken by Alexander, but only really speculation in regard to his motivations. This is because the extant ancient sources, for much of the’ whys and why nots,’ are not contemporaneous but rather lived, and wrote, around three hundred years after the death of Alexander. These surviving writings on Alexander, by Arrian, Plutarch, Diodorus of Sicily and Quintus Curtius, although they refer to earlier sources, like Cleitarchus, Ptolemy and Aristoboulus of Cassandrea, their works have not survived, so we are left with much supposition on the part of these writers; and debate by the modern scholarship that has come after, in their attempts to decipher the reasons behind the actions of a man who conquered the Persian Empire, and beyond, in 334-323 BCE.
In answer to the question, Alexander’s father, Philip II, had already begun the invasion of Persian territory before his death by assassination in 336. Alexander, as his successor, was now in charge of an army, previously led by Parmenion, who was leading an advance force and who were already in north-west Asia Minor. Macedon was a kingdom on the rise, recently united by Amyntas III, the highlands had been joined with the lowlands in the east, and Philip had built on this new stability to expand their borders militarily. New wealth came from these incursions into Thrace to conquer the Illyrians and Triballians, with the capture of silver and gold mines. Alexander had inherited, or possibly usurped, a militarily superior and politically hungry, expanding kingdom. As is often the case during times of succession, political instability had arisen within the region in response to possible perceived weakness in Alexander’s new reign. Arrian tells us, that there were uprisings in Thrace, and then Thebes, providing Alexander with military challenges, and as he was ruthlessly victorious in dealing with these, perhaps another spur to invade Persian territory. Also, when considering the possibility of Alexander, not continuing with this invasion, Plutarch, Quintus Curtius and Arrian provide reported evidence, which could be interpreted as ‘pressing financial reasons’ for Alexander to invade and then plunder Persian territory.
Then there is the liberation of the ethnically Greek, cities, in Asia Minor to consider, as impetus for Alexander to invade Persian controlled territory. The Persians had, historically, invaded, Hellas, in 480/79. Furthermore, in the Peloponnesian War, Sparta used Persian support to defeat Athens, and engaged in 386 in the first of a series of Common Peaces with the Persian Empire, which led to the loss of the Greek cities in Asia Minor to the Persians. Philip II, had established the League of Corinth in 338, and this politically inspired association imposed a sort of proto Hellenic nationalism to control cities like Athens and Thebes (before its destruction), fostering anti- Persian and anti-Spartan sentiment among their populations; and in Athens’s case conscripting their navy to the expedition . Alexander, as the king of Macedon, would likely, have seen himself, as the possible saviour of Hellenism in the region, and/or pragmatically used this for his own political advantage. Interestingly there were more Greek mercenaries fighting against Alexander’s forces than for, which casts some doubt over any thoughts of a universal consensus on the part of Hellas towards Alexander’s invasion.
Continued in Roman and Greek History by Robert Hamilton
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