But these are the three most significant, especially the Ptolemaic and the Seleucid. Now, what this establishes is what a lot of historians refer to as a new period of, especially this part of the world. When we go from shortly before the Persian invasions of Greece all the way to Alexander Great, we refer to that as classical Greece. But now we're going from classical Greece, classical Greece, with the death of Alexander and the beginning of the wars of the Diodeci for control, this sets up a new period, often referred to by historians as Hellenistic. Hellenistic. Hellenistic. Period.