Well Alexander was the first leader to use the technique of colonization, creating new cities based on Greek ideals in conquered lands. He also brought armies to engineers, architects, scientists, and philosophers, effectively spreading Greek culture across the world. And the main reason he was called great was because of his many conquests, for example: He crossed (334) the Hellespont (now the Dardanelles) and, as head of an allied Greek army, undertook the war on Persia that his father had been planning.
