Today in Middle Eastern history: the Battle of Heliopolis (640)

Our “Today in History” posts are always free, but if you want to support the newsletter and get the full Foreign Exchanges experience you know what you have to do:

The Arab conquest of Egypt was probably the first big surprise of the early Islamic period, after the Arabs’ initial military successes against the Byzantines and Persians, for a couple of reasons. First, while Egypt may be home to more Arabs than any other country in the world today, in the seventh century very few Arabs lived there, and virtually all of them were transient merchants. It was one thing for the Arabs to conquer Syria, Iraq, and the rest of the Levant, places that had already been settled by large numbers of Arabs. It was another thing for the Arabs to expand into Iran as the house of cards that was the Sasanian Empire crumbled. But expanding into Egypt was something more, and it demonstrated the scope of what the Arabs were capable of doing.

Second, after the Arabs took Syria and set the Sasanian court to flight, the Byzantines seem to have felt as though that would be it for a while, that they might get some time to regroup. Surely the Arabs would need to pacify and consolidate their huge initial gains, right? And that’s got to take some time. The Byzantines probably figured they would have a chance to recover a bit from double whammy of the devastating plague in the 540s (known today as the Plague of Justinian) and the nearly as devastating 602-628 war with the Persians. Once they’d caught their breath and put together a real, properly trained and prepared army, then they’d see how tough these Arabs really were.

Yeah. So…funny story.

We don’t have great sources for the Arab conquest of Egypt. We don’t have great sources for pretty much any early Arab conquests, really, but it’s especially acute in this case. But we do know that the conquest of Egypt happened a lot sooner than the Byzantines thought it would, and that’s in part due to one Arab commander: Amr ibn al-ʿAs (d. ~664). As was the case with another famous early Muslim general, Khalid ibn al-Walid, Amr was a Meccan who initially fought against Muhammad and his followers before joining the cause in 629 (he and Khalid supposedly went to Medina and accepted Muhammad’s message at the same time). He’s said to have been responsible for “converting” (I hesitate to use that word because Islam was still coming together as a distinct religion in this period, but oh well) Oman and then governed that region for a short time. Eventually, he joined the Arab armies that invaded Syria and Palestine. He was present, for example, at the Battle of Yarmouk in 636.

Map - Expansion Muhammad & Rashidun

Arab expansion through 661, including Egypt

In 639, as the Arabs were still picking through the remnants of the Persian Empire, we’re told that Amr asked the Caliph Umar (d. 644) for permission to lead a ~4000 man army into Egypt. Egypt, like most of the rest of the Roman Empire, had been whalloped by the plague and the war with Persia, which included a brief Persian conquest of Egypt before the Byzantines took it back. The war was devastating for all the reasons wars usually are, but the restorating of Byzantine control also hurt because, for that brief period under the Persians, Egypt’s Coptic Christians had actually experienced more religious freedom than they were permitted under the orthodox authorities from Constantinople. These people were not exactly thrilled to see the war end with a Byzantine victory. And the Byzantines were not really ready to defend the place against another invasion, busy as they were trying to beat the Copts back into grudging submission.

One thing that seems to come through in the histories of the Egyptian conquest, spotty as they are, is that Amr was familiar with Egypt to some degree. Again, Egypt wasn’t as familiar to most Arabs as was the Levant, but Amr had spent his pre-military career as a prolific trader and apparently visited Egypt for commercial reasons. As a trader, he may also have had imperial contacts feeding him information. It’s possible, then, that Amr knew how unsettled the province was. He certainly knew how rich Egypt was (the Nile Valley was still the breadbasket of the empire at this point). Whether he pitched Umar with talk of riches or of Byzantine weakness it worked, and the caliph authorized an invasion despite some apparent misgivings (see below). The size of Amr’s army raises questions about whether it was supposed to conquer Egypt or simply raid it and maybe establish a foothold that the Arabs could later exploit, but I suppose those questions are kind of irrelevant at this point.

There’s a story that has Umar changing his mind about the invasion and sending a messenger to Amr carrying a letter ordering him to turn back—unless, that is, he’d already invaded Egypt by the time he read the letter. Amr, in this tale, has not yet invaded, but realizes what’s in the letter and makes the messenger accompany him as he leads his army into Egypt and then reads the letter. This seems like a legend, but since it’s one that doesn’t make Umar look great in hindsight it’s possible that there’s a kernel of truth to it. It’s funny, anyway. The invasion now a fait accompli, Umar sent Amr around 12,000 additional men, which turned his small expeditionary force into an army that could really do some conquering. Amr met the reinforcements outside the city of Heliopolis.

Heliopolis was located roughly where Cairo is today. In fact, that city’s Ayn Shams suburb is built atop its ruins. One of the funny things about Cairo is that while it founded in 969, its site has been the location of important cities going all the way back to predynastic Egypt—first Heliopolis, later the nearby fortress at Babylon, and then Fustat, the garrison city that will be founded by Amr as his new provincial capital. All of those places are now part of modern Cairo. Heliopolis wasn’t so important by this point (Babylon, however, was, and that was probably the Arabs’ main target), but Amr decided to make it his temporary base because it was a defensible position with good access to water. It’s here that a ~20,000 man Byzantine army under the command of a general named Theodore decided, for reasons that don’t make a whole lot of sense in hindsight, to meet the Arabs in the open field.

Theodore, it seems to me, had no reason to do this. Amr’s army wasn’t well equipped for sieges and it could have been vulnerable to a Fabian strategy: harass the invaders from your well-fortified garrisons, hoard food inside those garrisons to deny it to the enemy army, then eventually make a major attack on a hungry, exhausted opponent. Theodore opted not to go that route. Worse, it seems he missed opportunities to attack Amr’s smaller force before it met up with those reinforcements at Heliopolis. But maybe he was relying on the fact that his army still outnumbered the combined Arab army to carry the day. Unfortunately, he was wrong, in large part because Amr thoroughly outclassed him as a general.

The night before the battle, Amr sent a small cavalry force to hide in nearby hills, with instructions to hit the Byzantine flank or rear once the battle started. He sent another detachment south to catch the Byzantines in their anticipated retreat. This all worked pretty much to perfection. The first detachment took the Byzantines completely by surprise and forced them to attempt an orderly retreat toward Babylon, while the second detachment ambushed them during the retreat and turned it into a rout. Almost the entire Byzantine army was killed or captured.

Without going too far beyond today’s topic, Egypt’s conquest at this point was probably inevitable. Babylon was able to hold out for a while—Amr’s army wasn’t equipped for a siege, remember—and capturing Alexandria, Egypt’s real crown jewel, took a while longer, but the Byzantines had just lost a 20,000 man army in one shot and were unable to raise another force large enough to either retake what they’d lost or defend what was still theirs. Amr became governor of Egypt and founded Fustat when Umar ordered him to base himself on the eastern side of the Nile rather than at Alexandria, as Amr preferred. He lost his governorship in 644, when Umar died and the new caliph, Uthman, appointed a close buddy to the job, but he got it back in 658 as a reward for backing Muʿawiyah during the First Fitna.