Now in future videos, we'll talk more about what happened in the Achaemenid Empire, but you can see the extent of it was pretty significant and it lasts for a little over 200 years until they are conquered by foreigners and the foreigners that conquer them are the Greeks. The Philip of Macedon's son, Alexander the Great, is able to on some level unify Greece and Persia and it's interesting because a lot of what we learn about ancient Persia, it's accounts from the Greeks, from folks like Herodotus, but during the time of classical Greece, Greece was really a bit of a sideshow. It was really this kind of thorn in the side of Persia. Persia was really where the power was, but as we get to the mid or the end of the fourth century BCE, Persia weakens, Greece unifies under Philip of Macedon and Alexander the Great and Alexander the Great is able to conquer the Persian Empire and he is short-lived. We have videos on Alexander the Great. I encourage you to watch them. His life is short-lived and his unified empire is short-lived but he has this dream of mixing the cultures and really being a unified people, but as soon as he dies, his empire splits, but the Persian Empire, for the most part, is in the control of the Seleucids and the Seleucid dynasty, this is essentially foreign rule because Seleucus, who establishes the Seleucid dynasty, he is one of Alexander's generals.