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Alexander the Great conquers Persia

How did Alexander the Great take over Persia? Sal explains.

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Video transcript

- [Instructor] So where we left off in the last video, we had Alexander the Great consolidating his power over the Macedonian Empire. And in particular, he puts down a rebellion in Thebes, destroys the city, which makes the other city-states of Greece say, hey, we're not gonna mess with this person anymore. And then Alexander says, I am now going to conquer Asia. I am now going to conquer the Persian Empire, do what my father wanted to do before he died. And so he puts one of his father's generals, now one of his generals, in charge of Greece, Antipater. Antipater, declares him regent, and then leads troops off to what many people say is have the greatest, or many historians call, the greatest adventure of all time. His attempt to conquer the Persian Empire and become the king of Asia. So the year is 334 BCE, and the first major battle that Alexander and his army encounters is at the Granicus River, here in modern-day Turkey. Now, keep in mind that Alexander's force, depending on what time we're looking at, it numbers between 40 and 50,000 troops, a good number of them infantry, some cavalry. And most of the battles that we'll see him fight, especially the next two against the Persian forces, he's hugely outnumbered. But at Granicus, he actually has an advantage in terms of the number of infantry he has. He's slightly outnumbered in terms of cavalry, but he's able to defeat the Persian forces. Now these Persian forces, they are significant. They're led by the Persian satraps, these are the governors of the territories, I guess you could say. The Persian regions or provinces in this area in Asia Minor. And he's able to defeat them. But as important as Granicus is, he still, Alexander still has not come directly against Darius III. Darius III is the Shah in Shah, the King of Kings, the king of Persia. And not to confuse Darius III with the Darius who 150 years before this attacked Greece. So now you have Alexander, his first decisive victory against the Persians. He makes his way down the Anatolian coast, in his mind liberating many of these cities that used to be Greek cities. Now if we zoom in a little bit, you can see the way this map is set up. Let me zoom in a little bit. Where you see these dotted lines around a city, this means that Alexander's forces siege the city. They surrounded it, they didn't let anything go in or out until the city surrendered. And so you see this path of Alexander and his forces. We then go into 333 BCE. Outside of the forward movement of Alexander and his troops and their ability to take over all of Asia Minor, modern-day Turkey in only a matter of a little more than a year, what also happens in 333 BCE, since some of you might have been wondering well, what ever happens to Sparta? Philip of Macedon never took over Sparta. Do they stay independent forever? And the simple answer is no. In 333 BCE, Antipater defeats the Spartans at the battle of Megalopolis and forces them into what we now call the League of Corinth. So let's keep now going back to where Alexander is. So Antipater clearly was competent at maintaining power in Greece. And the next major battle that Alexander and his troops face is at Issus. And what makes Issus significant is that they are hugely outnumbered. Historians disagree by how much they're outnumbered. Remember, we said Alexander's forces were around 40 or 50,0000, while the Persians at Issus, depending on which account you look at, were at least 150,000, probably over 100,000. More ancient accounts talk about many hundreds of thousands or even a million troops. What also made Issus significant is this is where, this is the first time that Darius III, the Shah in Shah, the king of Persia, directly confronts Alexander. Well, Alexander once again is able to, or at least here is able to overcome unlikely odds and defeat the Persian army, sending Darius into retreat. And he retreats so fast, he even leaves an encampment where his mother, his wife, and his two daughters are there. And Alexander then takes them captive, but treats them very nicely and then eventually marries one of the daughters. So after that defeat, Darius is on the retreat, or after that defeat for Darius, this victory for Alexander, Alexander then goes on into the Lavant, modern-day Syria and Lebanon and Israel and Palestine. And you can see he takes siege of the cities of Tyre and Gaza, but by the time he gets through that, it's now 332 and he makes his way into Egypt, and he's relatively unopposed. The satraps in Egypt to say, okay, you know what? We recognize you. They treat him as a liberator, and he even takes a pretty large detour to go to the Oracle for the god Ammon, and there he is reassured that he is a son of Ammon. And he already is told by his mother Olympius that he is the son of Zeus, and so many people call Alexander, or he calls himself now, Alexander Zeus Ammon, the son of Zeus Ammon. So once again he's trying to really make himself, or maybe he believes himself, that he is half god, that he is a demi-god. But then he continues on with this, I guess you could say grand adventure, and I don't want to romanticize it too much because even though he is in some way conquering and/or unifying these large areas, there's also a lot of bloodshed, a lot of civilians dying. This is a very ugly thing that only looks romantic from maybe a distance of many thousands of years. But when you think about it, it would not have been very pleasant to have lived in any of these cities that Alexander and his troops are going through. But then he leaves Egypt, and the whole time after the defeat of Issus, Darius keeps sending him treaties to say hey, maybe we can work this thing out. Maybe you can just stop to the west of the Euphrates. I'll give you this or that. But Alexander keeps saying nope, not for me. I want to be the king of Asia. There's only one king of Asia. And so they eventually meet again at Gaugamela. Once again, a very significant battle in history where once again Darius is there and has a significant force advantage over Alexander, and this time doesn't make the mistake of meeting him in a relatively narrow area where his force advantage won't really be an advantage. But even at Gaugamela, Alexander is able to decisively defeat him. And Darius has to flee over the mountains to Ecbatana. My apologies, 'cause I know I'm probably not pronouncing it perfectly. And Alexander and his forces then go on to capture Babylon and Susia, and Susia was actually one of the capitals of the Achaemenid Empire. So this whole way they're able to get all of this treasure and start sending it back to Greece. And then, we eventually get to, and by this point having been defeated at Issus and now Gaugamela and being on the run, the Persian Empire is, you could say it's already fallen, or it's definitely falling, but it becomes really official once we get to 330 BCE. And remember, this is less than five years since Alexander started, and that's short by any time frame. But they're on foot and on horseback. This is not modern warfare where they have tanks and trucks and planes. And the facts are conquered so much territory and empires over 200 years old in this short about of time frame is kind of breathtaking. But it's in 330 where the forces go to the Achaemenid capital of Persepolis, the capital for over 200 years, and they sack that town. And not only do they sack that town, they destroy the town. And I'll repeat it again, Alexander the Great, he's romanticized a lot, he's called the Great, but they destroy that town in a way that you would not make your parent's proud. Let's just put it that way. But at that point he is now king of the Persian Empire. Darius is officially on the run. And what Alexander now cares about is continuing this adventure, continuing it east into what we now consider to be Afghanistan, Turkemenistan, Uzbekistan, and modern-day Pakistan. He also wants to get Darius. Some would argue he wants to kill him himself, some would argue that he wants to somehow have Darius declare Alexander as the rightful Shah in Shah, king of Asia. And so you can see the path of Alexander and his forces. After they destroy Persepolis, they then go up, they turn northwards. They go through all of these cities up here. Then in 329, they're on, they're following the trail of Darius. Darius eventually gets captured and killed by one of his satraps, someone by the name of Bessus. And Bessus, who is one of the satraps of Bactria, kills Darius and declares himself Artaxerxes V. He wants to be the Shah in Shah. Well, eventually Alexander catches up with Bessus in 329. He's really angry that Bessus has killed Darius. He's also likely angry that Bessus is claiming that he is the Shah in Shah. And so he kills Bessus in fairly brutal form. And there's different accounts of how the killing happened, but all of them are various degrees of brutal. But from there Alexander's troops continued on eastward, continued on eastward into what we now consider to be Afghanistan and Pakistan. And there he has the famous battle with the king of Porus where he encounters these 200 war elephants. But once again he's this great military tactician, and he's able to defeat the king. And along this whole way it's worth mentioning he sets up all of these towns, he sets up 20 Alexandrias. And near here he even sets up a town named after his horse Bucephalus, the town of Bucephala. And Alexander is eager to keep conquering. Once he defeats the king of Porus, he says, hey, I want to go conquer the rest of India. But his troops are far from home and they are tired and they are spread thin and they're getting sick. They are not so interested in that. So eventually Alexander says, all right, I'm with y'all. Let's go back. And the troops are really, really happy. They make their way back. You can see the path back after, and you can see as they follow the Indus River in Pakistan. And eventually we get to 323 BCE, and Alexander is back in Babylon. And it's over there in Babylon that Alexander dies at the ripe old age of 32. It's mindblowing to think about how much happened in the 12 years that he was emperor of the Macedonians or even the Shah in Shah of Persia. He was able to defeat an empire over 200 years old. And what's significant about this is that as he conquered, he encouraged his troops to assimilate. In fact, he was criticized for maybe assimilating a little bit too much. But he dies in Babylon, and it's not clear exactly why he dies. He was a major drinker. Some people say alcohol poisoning. Some people say it was direct poisoning. But needless to say, this was one of the most significant decades in human history, this conquest of Alexander the Great.