What were Alexander the Great’s conquests

He took the areas which are now called Turkey, Syria, Lebanon, Palestine, Egypt, Mesopotamia, Persia, Central Asia, Afghanistan and Pakistan. These areas he placed under Macedonian or local governors. He was planning to go into the western Mediterranean when he died, a move which would have pitted him against Rome and Carthage.

After his death the empire was divided and ruled by his generals who fought spasmodically with each other. The eastern conquests progressively reverted to native rule.

Footnote:

There is an interesting discrepancy in the list of conquests – his alleged defeat of Porus in India hardly fits in with the circumstances:

After defeating Porus he gives him the kingdom back and inexplicably adds the kingdom of his own loyal Indian ally Taxiles plus other territory which more than doubles Porus’ kingdom.
He then helps Porus by defeating local rival tribes and cities for him.
He goes home with his army, leaving Porus in control – a lot of pain for no gain.

This is hardly the action of an absolute conqueror who is attempting to take over the whole eastern world, no matter how generous of spirit. An alternative explanation is that the battle was lost by Alexander, or at least a standoff, and Alexander secured his own withdrawal by aiding Porus first. This is speculative, but the stories which are accepted as historical claim Alexander’s total supremacy are at odds with the evidence. It has the hallmarks of a cover up, today we would call it spin, and the story and Alexander’s invincibility need to be approached with caution.