Hellenistic Greece

The nominal start of the Hellenistic period is usually taken as the 323 BC death of Alexander the Great in Babylon. During the previous decade of campaigning ( from 334 BC ), Alexander had conquered the whole Persian Empire, overthrowing the Persian King Darius III. The conquered lands included Asia Minor, Assyria, the Levant, Egypt, Mesopotamia, Media, Persia, and parts of modern Afghanistan, Pakistan and the steppes of central Asia.
Alexander had made no special preparations for his succession in his newly founded empire, dying as he did at a young age, and thus on his death-bed (apocryphally), he willed it to "the strongest".^[5] The result was a state of internecine warfare between his generals (the Diadochi, or 'Successors'), which lasted for forty years before a more-or-less stable arrangement was established, consisting of four major domains:
source: wikipedia