The caliph chose the location, thirty miles upstream from the Persian capital of Ctesiphon, on the banks of the Tigris at the narrowest point between it and the Euphrates. Three astrologers, an ex-Jew from Basra, an ex-Zoroastrian and a muslim, selected the date to start construction: 30th July 762. Three years later it was deemed officially finished, and forty years later it was the most populous city on the planet.
The layout of the central citadel was a perfect circle, as Persian capitals had been (including Ctesiphon before the arab armies destroyed it a century previously). To the locals this must have been, to all intents and purposes, the next incarnation of the Persian Empire.
There were two crucial differences, however. The man living with his harem in the citadel was not a shah but a caliph. And he adhered to the new religion of the arabs rather than the one that had dominated Persia for the previous two thousand years: zoroastrianism. He was a muslim, and as caliph he was the official successor of the Prophet who had died six generations earlier, in the year 632.
This meant that the zoroastrian priests were without a job. They had two thousand years’ worth of learning to draw on, and almost nobody to pass it on to. It wasn’t obligatory to convert to islam, but your career prospects at court probably got a boost if you did.
The muslims continued the Persian dedication to learning, however, and even expanded it. Under the Sassanid Empire (which fell to the arabs in 638) the main seat of learning had been the academy of Gundeshapur, a few hundred miles to the east. The caliph in Baghdad indicated that he was interested in promoting scholarship. Scholars from Gundeshapur relocated to Baghdad.
Not only zoroastrians came to Baghdad. The largest christian church in the world at the time (in terms of geographical extent) had centres in Nisibis, a few hundred miles to the north, Merv in Khorasan to the east, and Gundeshapur. A century or so earlier the church in Constantinople started enforcing its orthodoxy more rigorously, and many christians moved to join the church of the East, whose headquarters were then in the sassanid capital of Ctesiphon. When the arabs sacked Ctesiphon in 641 the catholicos (equivalent of the pope in the latin roman church) moved north, nearer to Nisibis. Once Baghdad was established, the Church of the East relocated its headquarters there. In 780 the catholicos Timothy I was invited to meet the caliph, maybe because he had translated Aristotle’s ‘Topics’ into arabic, and maybe because the caliph wanted to discuss religion with him. Thus began a sometimes mutually profitable and sometimes uneasy relationship between the Church of the East and the caliphate that continued for several hundred years. In the good times christians were viziers, doctors and translators. In the bad times they were persecuted.
But on the whole the Church of the East thrived in the new abbasid empire as it had done with the sassanids. It already had missions further east, beyond the muslim empire into India and China. These were consolidated and confirmed. Five hundred years later, when the Mongols sacked Baghdad, the christian residents were spared from the slaughter because the khan’s wife and mother were both christians, members of the Church of the East.
The jews were there too, as they had been since the Babylonian captivity a thousand years before. When they had the chance to return to their homeland, many opted to stay in Mesopotamia. In the towns of Sura and Pumbedita, both on the Euphrates River, the definitive version of the Talmud, the commentary on jewish law, had been compiled, completed a century earlier.
The arabs, adherents of the newest religion in the region, were based at Kufa and Basra. In this period the arabic equivalent of the Talmud, the Hadiths, were compiled in these towns.
History books often aim for a tidy storyline, one that is simple, accessible and reasonable. But as each of us knows from our own experience, real-life events are not so tidy. I wonder how much, at the time, people saw a clear distinction between adherents of these four and the other religions swirling around the area. Other religions included the Manicheans (whom the arab scholars decided were not ‘people of the book’ and so liable to persecution), the Sabians (mentioned in the Qur’an but even a century after it had been written, it was forgotten who exactly they were), as well as other gnostic sects and Buddhists and Hindus from further east. Another important centre of learning at this time was Harran, not far from Nisibis. In order to escape the fate of the Manicheans, the inhabitants of Harran declared themselves to be the descendants of the Sabians.
How much did these educated people interact and influence each other? How many under-employed zoroastrian priests, jewish rabbis or christians offered a hand to encode the sayings of the prophet? Sura is only a few miles downstream from Kufa, after all.
Here is an example of the confusion. The abbasids had defeated the ummayads, the previous dynasty, around 750 with the help of a remarkable man. The man’s real name is not known, but he called himself Muslim abu Muslim ibn Muslim: Muslim, son of muslim and father of muslim. A pretty clear statement of one’s credentials, one would have thought. He launched his campaign in the town of Merv in Khorasan, a campaign to overthrow the ummayads and set a member of the Prophet’s family as caliph. The best candidate they had was a descendant of the Prophet’s uncle Abbas. Hence the abbasids.
Once installed, the new abbasid caliph had his own agenda, which did not include Abu Muslim. He invited him to dinner, and had him killed. This was not well received back in Khorasan. Several further insurrections against the abbasids were brutally put down by the caliphs’ armies.
But here is the curious bit. The rebellions were led by self-declared zoroastrians, who claimed loyalty to or discipleship from Abu Muslim. Our tidy narrative of different religions starts to feel somewhat frayed. If you want to investigate this further, two of those rebels were Babak Khoramdin and al-Muqanna.
One fact is indisputable however: Baghdad prospered. The translation movement, with help from scholars from all of the cities named here, went into a higher gear. The golden age of islam took off.
It must have been an exciting place to be. A delegation from India (maybe via Gundeshapur) brought their latest cutting-edge mathematics, systematised a century previously by the great mathematician Brahmagupta. This included the concept of zero as well as the decimal system of nine numbers and the sine function. The numbering system currently in use in this world was the Babylonian one of base-60, which lives on in our measurement of seconds, minutes and the degrees of a circle.
The Indians also brought the game of chess, which was then adapted to local tastes. Chess pieces look as they do today because they were depersonalised to avoid muslim sensitivities about depictions of the human form. The word ‘checkmate’ comes from the Persian ‘shah-mat’, ‘the king is dead’.
The first home-grown scientist of the golden age was Jabir ibn Hayyan, remembered as Geber the Alchemist, the founder of the science of chemistry. He probably lived in Kufa and almost certainly spent time in the new Baghdad. He wrote prolifically. He developed theories of what matter is made of, partly based on received learning and part on his own researches. He advocated experimentation as a way to learning. However, much of his writing was so obscure that the word ‘gibberish’ was coined a few centuries later, meaning ‘as impenetrable as the works of Jabir’.