Language, it is truly the most amazing of human inventions; how a group goes from grunting about the location of the ripest fruit to composing poetry and debating philosophy is, without a single doubt, our race’s most underappreciated miracle. Small wonder that people have always attributed such arts to various gods and muses.
When the army of Alexander left Greece (Hellas) set out across the Hellespont in BE56, there were already more dialects, regionalisms and variations of what would be considered Greek today than could be counted. Aeolic, Doric, Ionian, Attic, Laconic...when one is mustering an army from every corner of Hellas; from Crete, to Thessaly, to Macedonia itself, you are dealing with one hundred dialects spoken one hundred different ways. How could such an army communicate? How could officers relay orders correctly and ensure the now-famous army coordinated as well as it did in engagements such as Granicus and Gaugamela?
The answer came in the form of Koinè. Koinè, or 'common Greek' seemed to evolve organically. Though there were many differences between the dialects spoken by the army, there were enough commonalties for the men and women of the host to understand at least the basic gist of what they said to one another. However, for subtleties of meaning and exactitude of instruction that was not, of course, good enough. For things such as stories of one another's heroics, amorous exploits and godliness of lineage, it is assumed by our later chroniclers that the soldiers simply started picking up words and phrasing from one another. After a while certain terms and words became, for want of a better word, standardised.
As Spartans mixed with Athenians, Mollosians with Thebans, Macedonians with Thracians, it became much simpler to use a form of speech that everyone understood. Simply put, the soldiers simply agreed to say things a certain way and, over time, such tacit agreements spread and metamorphosed into what we came to know as Koinè; a new and standardised language which, for a time, became the glóssa koiní of the highly diverse army.
After the battle of Gaugamela and the Night of a Thousand Weddings at Susa, Alexander began his somewhat unpopular policy of recruiting new soldiers from the recently conquered territories. By this time, Koinè was already standard among the Greeks in the army but now, there were various Persian dialects to consider.
Out of respect for their new countrymen and, perhaps, fear of their new Emperor, the Persians began (with varying degrees of success) to learn to speak the prevailing language of the army.
Then, following the near disaster on the Hydaspes and Gedrosian Desert, recruitment of those considered 'foreigners' was stepped up to replace the heavy losses of the Indian campaign. Let us not forget the near-mutiny at Babylon following Alexander's brush with death. A large contingent of mostly Macedonian veterans was sent home with Perdiccas to "garrison against possible sneak attacks from broken fleet elements on our unprotected back." Really it was a political move to get the firebrands away from the fuel.
Once the army headed North from Babylon towards to frozen wastes of the horse tribes, the army was vaster than ever before and no longer predominantly Greek.
Nobody knows how it began but a new language began to emerge.
In the army there were now thousands of nations represented; Persians, Sogdianians, Scythians, Bactrians, Assyrians, Akkadians, Ethiopians, Egyptians, Carthaginians, Phoenicians, and many others. Some of them learned Greek but they were a fighting force and did not really have time to stop along the way to construct scholeía to instruct them in the finer points of language!
Now, campaigning and entering into battle with a force exceeding six million fighting men (and women) when less than half of that force understands you in more than the most basic if fashions is challenging to say the least.
Once again, the soldiers figured it out as soldiers are wont to resolve problems; simply and surprisingly effectively. A few people died of course, misunderstandings are common among warriors and usually resolved in that simple and direct way of theirs, but fewer than one would expect. Alexander's decision to appoint Persian officers actually accelerated this already rapidly organic process.
The result was known as the argot among the army; described as "the bastard offspring of such a korakun mess as to make the most extreme Bacchic Kómos appear tame..." by General Clietus in one of his more sardonic moments.
The argot consolidated and crystallised on the tough journey through the frozen Hemodos mountains and the "Day of the Ten Thousand". After the Kalshodar arrived, the varied remainder of the army had reason to cohere. Those that became known as the "Regular Irregulars" had something to prove and they had someone to prove it to; the Kalshodar. The Regular Irregulars were afraid that the Kalshodar could easily replace them and that they would be disbanded and either sent home or left behind in a garrison. The result of this was the creation of the very camaraderie which had been missing for all this time, an end to all the friction and nationalism. No longer were they Greeks, Macedonians, Persians, etc., now they were Alexander's Army and they made efforts to count as a fighting force; to prove they were still needed.
Part of those efforts was the argot, a curious melding of all the disparate languages spoken throughout the army into something very new and different. It spread to the 'hangers on' of the baggage train of non-combatants and even to the Kalshodar themselves. Alexander made the very wise decision to recruit his administrative staff into formalising the argot into Empyraen Standard Greek or Là Glòstean Empyrean; a tongue born from Mother Greece but deeply coloured by the new citizens of the Empyraeum.
It was perfect, Alexander said, to formalise a new tongue for a new world. A tongue made up of all the languages of the old.