What was Alexander the greats major accomplishment?

Answer 1

Alexander the great's major accomplishment was to do so much in such little time -- and with such a lasting effect. In roughly ten years and with a small force of soldiers, he conquered the world's largest and most powerful empire which mustered troops vastly superior in numbers to Alexander's own. The conquests continued even beyond, with further success against other opponents, and included cultural conquests as well as military. Moreover, these achievements lasted for centuries.