The Indian campaign of Alexander the Great began in 326 BC

Alexandria is one example of the cities Alexander the Great founded throughout his expansion.

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The Greeks in the Macedonian train were mobilized by the Macedonians, and historians and speak of them as hostages that would ensure the good behavior of their countrymen left behind in Greece under the watch of Antipater's Macedonian garrisons. Not surprisingly, the Greeks in Alexander's army did not have significant role in the upcoming battles, only to be discharged when convenient.

The greatest of Alexander's battles in India was at the river Hydaspes, against king Porus, one of the most powerful Indian rulers.

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That might explain why Pausanias was instantly put to death by Alexander's close friends as he attempted to flee the scene, instead of being captured alive and tried before the Macedonian assembly. Philip, the great Macedonian conqueror was dead, the man who liberated his own country and brought if from the edge of the abyss into a world power.

Callisthenes was soon executed on a charge of conspiracy, and we can only imagine how Aristotle received the news of his death. The two were already estranged for a long time before Callisthenes’ execution, as Alexander's letters to his former tutor carried unfriendly contents.