The righteous beat me [in] kindness. And reprove me, My head does not disallow oil of the head, For my prayer [is] still about their distress. [source]
14 October 2025
The Last of the Geonim
14 May 2025
Charlemagne and the Arabic World
In the Life of Charlemagne written by Einhard, and a few other Latin/Frankish sources, we find references to the Carolingians reaching out to the Abbasids. The Franks had clashed with the predecessors of the Abbasids, the Umayyad Caliphate, most notably at the Battle of Tours in 732. The Umayyads were finally expelled from Gaul by Pepin the Short.
After the collapse of the Umayyads and the rise of the Abbasids, Pepin reached out to Caliph al-Mansur. The Carolingians were powerful enough in Western Europe at that time that the Abbasids were open to the possibilities of an alliance; Umayyads still existed on the Iberian Peninsula, posing a potential threat to the southern border of the Carolingians and the western border of the Abbasids.
A Carolingian embassy visited Baghdad in 765 and returned with gifts after three years, followed by an Abbasid embassy to France in 768. Arabic coins from that era are found throughout the Carolingian world, and Arabic gold was exchanged for materials like timber and iron; also, slaves went eastward.
The alliance included a request from the Abbasids in 777 for military aid against the Umayyads in Cordoba. Charlemagne crossed the Pyrenees into Iberia in 778 with a large force, joining in Zaragoza with the Abbasid forces of Sulaymaniyah al-Arabi in an attempt to reconquer the peninsula. This was unsuccessful, and on Charlemagne's return to the north he was ambushed disastrously by Basques at Roncevaux.
Charlemagne did not give up on an alliance, however, and had a strong relationship with Harun al-Rashid, who gifted Charlemagne an elephant, recorded in the Royal Frankish Annals as Abul-Abbas. A few embassies went back and forth between the courts of Charlemagne and al-Rashid. (The illustration is of al-Rashid receiving a Frankish embassy.)
A few centuries later, France saw value in another alliance to the east, with the Mongol Empire. The reason and the result will be tomorrow's topic.
13 May 2024
Great Mosque of Samarra
One of his projects was a huge mosque in Samarra along the Tigris River. His desire for ostentatious displays of wealth and devotion made it the largest mosque in the world at the time, and it was completed in only three years.
The minaret (shown here) is 171 feet high and 108 feet wide, the top reached by a spiral ramp. It is all that remains of the original structure. The main building was constructed from baked brick octagon piers with four columns in the corners of imported marble. It had 17 aisles, and the walls were covered with dark blue tiles.
A total of 16 doors allowed the faithful inside, where light was provided by 28 windows, 24 of were oriented by the qibla, the direction to face when praying. A fountain in the center was believed to be carved from a single stone and delivered by elephants. That had been commissioned by al-Mutawakkil's predecessor, his brother al-Wathiq. The baked brick ceiling was 35 feet high, supported by 464 pillars.
In 1278, the mosque (but not the minaret or outer wall) was destroyed when Iraq was invaded by Hulagu Khan's Mongols. A restoration process started in 1956.
The construction of the Great Mosque was part of a plan to make Samarra the center of an expansive urban area, so there were other projects in the area. Part of this expanded area was named al-Mutawakkiliyya for himself. Another new city he founded needed water, and he commanded two courtiers, the brothers Muhammad and Ahmad ibn Musa, to make it happen. They ignored local engineers and turned instead to al-Farghani, an astronomer. He was very smart, and a good mathematician with a good reputation, but he made a tiny mistake with great consequences. That's a story for tomorrow.
12 May 2024
Ending Religious Tolerance
When al-Ma'mun died in 833, he nominated his brother rather than his son to rule. When al-Mu'tasim died, his eldest son (Ja'far's brother al-Wathiq) became caliph. al-Wathiq had a fairly non-dramatic reign except for ongoing battles with the Byzantine Empire. al-Wathiq ended that conflict for several years after agreeing to a prisoner exchange in 845. His death from natural causes in his mid-30s caught the nation by surprise. His son was fairly young, and so for the second time in that dynasty the succession went "sideways" to a brother rather than a son. Ja'far found himself elevated to the caliphate and taking the regnal name al-Mutawwakil ala Allah, "He who relies on God." He was 26 years old. (The illustration is of his face on a silver dirham.)
His well-educated brother had been a lover of poetry and the arts, enjoying poets, scholars, and musicians. In contrast, al-Mutawwakil cared more for power and grandiosity. His reign was known for ending the religious tolerance of his predecessors. Whereas dhimmi ("protected ones," a designation given to those of other faiths) had many privileges, he took steps to revoked or disrespect them. In 850 he decreed that all Jews and Christians had to wear garments that distinguished them from the faithful: honey-colored (yellow) hoods and belts. Moreover, their places of worship were destroyed and they were no longer allowed to hold public office.
An ancient sacred cypress of the Zoroastrians was ordered cut down to be used as timber for a new palace. It was 1400 years old, and legend said it had been brought by Zoroaster from heaven.
He even attacked fellow Muslims. There was on ongoing debate over whether the Koran was created or not. That is (to put it simply): was it produced by a man, or was it divine knowledge that was then "un-created" by a man, because it was eternal? There was a sect that rejected the idea that the Koran was the literal word of and co-eternal with God, and therefore did not exist until Muhammad wrote it. al-Mutawwakil stomped on this heavily, taking hostile steps to anyone promoting the doctrine that the Koran was created by a man.
al-Mutawwakil had named his eldest son, al-Muntasir, as his successor, but over time was showing favor to his second son, al-Mu'tazz. The two sons had support from different political factions, and the elder was unhappy with his father's shifting attention, especially when the younger was given the privilege of leading prayers at the end of Ramadan. Other humiliations followed, and a faction approached the elder son with a plan to assassinate his father. al-Muntasir was not opposed. The plan was carried out in December 861, and al-Muntasir became caliph. al-Mutawwakil had died before lumber from the Zoroastrian cedar arrived to be used.
Unfortunately, this began a period known as the Anarchy at Samarra, lasting until 870 and almost destroying the Abbasid Caliphate.
Let's turn away from politics and find something good about al-Mutawwakil's reign. How about the Great Mosque of Samarra? I'll bet there are some interesting stories there. I'll check it out and get back to you tomorrow.
29 November 2023
The Maintenance of Health
The original was organized in synoptic tables: a way to present data in a simple and condensed manner, previously used for astrological tables. Ibn Butlan used them to present not just ways to treat illness and to maintain health, but also ways to prepare food and how and what to grow for health. Later manuscripts were lavishly illustrated, especially after the 14th century. (The illustration is of a facsimile edition made in 1986.)
Ibn Butlan set out the essential elements of health and well-being:
- sufficient food and drink in moderation
- fresh air
- alternations of activity and rest
- alternations of sleep and wakefulness
- secretions and excretions of humors
- the effects of states of mind
If one is not paying attention to these elements, illness occurs.
The Tacuinum includes lists of many vegetables, fruits, nuts, and herbs that are good for treating certain conditions. It also includes the dangers of excess consumption. As the manuscript was copied and distributed, changes were made, and not every copy includes every list. Some added remedies that were not in the original.
The word "humors" was italicized in Ibn Butlan's list because I wanted to draw attention to it. I've ignored discussing the medieval idea of humors for over a decade because I assumed people have already heard of them and I want this blog to focus on all the things that are not generally known. Of course, the details of humors are probably worth talking about. See you tomorrow.
26 August 2023
Jabir ibn Hayyan
His name was Abū Mūsā Jābir ibn Ḥayyān, and he lived in the 8th century...we think. To be fair, he does not get mentioned until the 10th century by a Baghdad bibliographer who said Hayyan was a disciple of the Shi'ite Imam Ja'far al-Sādiq (who died in 765; Haiyan's writings refer to al-Sādiq as "my master"). That biographer assured his audience that Jabir existed, and made a list of his works, although many later Shi'ite biographers never mentioned Hayyan, and it is considered unlikely that he wrote the many hundreds of texts attributed to him.
Someone had to create the writings attributed to Hayyan, however, and perhaps the name was a pseudonym used to avoid the potential negative publicity because it looked like alchemy, which was rejected by many. Also, the works attributed to him are so many and varied that it is difficult to believe they were the work of one man. He may have inspired a "workshop" of students and followers who produced many of the works. Despite the confusion about his existence, a 271-page biography was written in the 20th century, and is readable at the Library of Congress website (if you can read Arabic, that is).
The body of work includes many techniques that are familiar to any high school student who has taken Chemistry: precipitation, crystallization, and distillation. It also teaches procedures for making apparatus (see the illustration) and equipment, for improving the quality of products such as steel, and how to reduce oxidation in metals. We learn from them how to dye and waterproof cotton and leather, the purification of gold, and how to treat cinnabar to extract pure mercury.
You may notice, in large sheets of glass used for, say, store fronts, that there is a greenish hue (most visible if you look at the edge of the glass sheet). Hayyan's writings explain how manganese oxide can be added to glass production to eliminate the greenish hue, resulting in a perfectly clear pane. These writings provide most of what is known about chemical analysis until the 16th century.
I want to go back to the question of Haiyan's identification. One of his writings implies an association with a certain family, the Barmakids. His 10th century biographer, Ibn al-Nadīm (c. 932–995), reports that Hayyan was devoted to Jaʿfar ibn Yaḥyā al-Barmakī, an Abbasid vizier. You may not recognize that name, but I promise you that you have heard of him. In fact, I promise 1001% that you have heard of him. With that teaser/clue, I'll see you tomorrow.
10 May 2023
The Reconquista—Abbasid Alliance
Sulayman al-Arabi, the Abbasid-preferring governor of Barcelona, sent a message to Charlemagne in 777, offering his submission to Charlemagne's rule if he could get military aid against the Umayyad emir of Córdoba, Abd ar-Rahman I. Sulayman had allies: Husayn of Zaragoza and Abu Taur of Huesca. Charlemagne was all too happy to bring an army south to reconquer territory from Muslims.
Reaching Barcelona, Sulayman welcomed him, and their two armies marched next to Zaragoza to add Hosayn's military forces. Reaching Zaragoza, however, they found that Husayn would not allow them into the walled city. He had just recently defeated Abd ar-Rahman's general and taken him prisoner. Husayn was willing to rely on his own power to deal with further Umayyad threats, and no longer was willing to risk his autonomy being usurped by a Christian ruler.
Charlemagne settled into a siege of Zaragoza. After more than a month, however, an agreement was made: Husayn would pay Charlemagne some gold to go away. This he did, but on his way back north Charlemagne decided to make an example of the Basques, whom he suspected of being allied with the Moors. He spent some time destroying villages, tearing down the walls of Pamplona, and setting up his own garrisons. Satisfied, he set off for home through the Pyrenees.
Unknown to him, the angry Basque forces organized and pursued. Not only had this attempt at Reconquista come to naught, but Charlemagne was about to be handed a terrible defeat that would be immortalized in literature. Details tomorrow.
04 September 2014
Mamluks & Mongols
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[source] |
Mongol hordes were ruthless when taking over a new territory. Iran's resistance required such force to subdue that much of the country's agrarian infrastructure was destroyed, causing famine and serious population loss in the years following the wars.
The Mongol Empire had benefits, however, to others as well as itself: an enforced peace throughout this realm made travel and trade safe for foreigners as well as residents. Given time, they might have conquered—and therefore united—North Africa and Europe as well. For the first time in their history, however, they were stopped, defeated when they encountered the Mamluks.
Hulagu, a grandson of Genghis and brother to Kublai and Möngke, managed the southwestern front of the Mongol Empire, moving from Persia toward Egypt. He took down the Assassins, and conquered Baghdad by defeating the Abbasid Caliphate. He then sent a message to Qutuz in Cairo, advising him to submit to Mongol rule. Qutuz killed the messengers and stuck their heads on one of Cairo's gates.
Then word came that Möngke Khan had died, and Hulagu took much of his army back home to lobby for the throne. When Qutuz learned that a much smaller military force had been left behind in the Middle East, he gathered his Mamluk army and marched out of Cairo. Two armies of about 20,000 men each met on 3 September 1260 at Ain Jalut ["Spring of Goliath"] in Galilee.
The Mongol army did not know the territory as well as the Mamluks did (Qutuz had allied himself with a Mamluk leader from the region who knew it well and planned their strategy). The Mamluks played a "hit-and-run" game, then pretended to retreat, luring the Mongol army to follow them into the highlands where the largest part of the army was hidden, its archers waiting to ambush the Mongols. Although the Mongols rallied somewhat, they were unable to gain the upper hand. For the first time, their forward advance to expand their territory was stopped, placing a western border in the face of Genghis Khan's dream of a worldwide Mongol empire.
The Mamluks had another advantage: explosives, specifically hand cannons. Hand cannons were metal cylinders packed with gunpowder and set off with a flame. They were not good for aiming projectiles with any kind of accuracy, but in the Battle of Ain Jalut they were used to startle the opposing cavalry mounts and create confusion.
03 September 2014
Who Were the Mamluks?
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Mamluk going to war, from a 14th century History of the Tatars |
Mamluks, taken from their families and raised under strict military and religious discipline, were extremely loyal to their owner and supportive of their comrades. The lifestyle and privileges they enjoyed were such that some Egyptians would get themselves sold into slavery to be trained as Mamluks, ensuring a steady career.
Although very few people today know about the Mamluks, we owe them a debt for saving the West from the grandson of Genghis Khan...but that's a story for tomorrow.
30 July 2014
The Founding of Baghdad
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The red pin is Kufa, the purple pin is Baghdad, about 170 km north. |
Although the date of its founding is accepted as 30 July 762, building Baghdad took 100,000 workers from 764 to 768. The location of the city on the Tigris was beneficial: the abundance of water throughout the city encouraged growth that allowed for all residents to have easily accessible water. By the 9th century, Baghdad had grown to be the largest city in the Middle East, with a population between 300,000 and 500,000.
The entire city complex was originally built as a circle about 19 kilometers in diameter and was nicknamed al-Mudawara ["Round city"]. The wall was built to last: it was about 44 meters thick at the base, and about 30 meters high. Al-Mansur brought together artists as well as engineers to build his capital, and the circle included parks and promenades, gardens, and a mosque at the center. The city walls had four gates called Basra, Khorasan, Kufa and Syria, named for the places that the highways from those gates led to.

The strength of the Abbasid Caliphate started to deteriorate due to religious and regional strife. A grandson of Ghengis Khan (but not Kublai, well-known to Marco Polo fans) managed to sack Baghdad in 1258, destroying much of what made it great in learning and art and religion. The city was further devastated in 1401 by Tamerlane.
29 July 2014
The Abbasid Caliphate
That means that the Abbasid Caliphate was "in charge" during many of the Islamic interaction with Europe mentioned in this blog:
- Abu Ma'shar, the Father of Arab Astrology, who brought commentaries on Aristotle to Western Europeans
- The astronomer Abd al-Rahman al-Sufi, who reconciled Greek and Arab star charts
- Averroes the Commentator
- Avicenna the surgeon
- ...and, of course, it was during this time that Algebra came to be
Besides math and philosophy, the Abbasid Caliphate was at the forefront of technology, adopting the use of Chinese paper-making techniques and gunpowder. Arabs developed the sextant, windmills for industrial use, and kerosene from petroleum.
The Abbasid's first capital was Kufa, on the banks of the Euphrates, but they shortly chose a different city, whose only shortcoming was that it did not exist.
On 30 July, 762, that would change; but that's a story for tomorrow.