History of The Abbasid Caliphate and The Golden Age of Islam

Illustration of the round city of Baghdad

Abbasid Caliphate

The Abbasid Caliphate was the third caliphate to succeed the Islamic prophet Muhammad. A dynasty founded it descended from Muhammad's uncle, Abbas ibn Abd al-Muttalib. The Abbasid Caliphate first centred its government in Kufa, modern-day Iraq, but in 762 the caliph Al-Mansur founded the city of Baghdad. The Abbasid period was marked by dependence on Persian bureaucrats for governing the territories as well as an increasing inclusion of non-Arab Muslims in the ummah (Muslim community). The Abbasid Caliphate overthrew the Umayyad caliphate in 750 CE and reigned until it was destroyed by the Mongol invasion in 1258.

Illustration of The Abbasid Caliphate

Illustration of the map of the Abbasid Caliphate. The Abbasid caliphate was one of the largest and most influential Islamic states in history. It spanned from North Africa to Central Asia and reached its peak of expansion in the 9th and 10th centuries CE.

Golden Age of Islam

The Golden Age of Islam is often taken to be a period of scientific, economic, philosophical, cultural, and scholarly prosperity in Islamic civilization, estimated to be between the 8th and 13th centuries. This period is most commonly marked by advancements in mathematics and the sciences, as well as inventions in medicine and astronomy. This period is traditionally understood to have begun during the reign of the Abbasid caliph Harun al-Rashid (786 to 809) with the inauguration of the House of Wisdom. Scholars from all over the Muslim world flocked to Baghdad, the world's largest city by then, to translate the known world's classical knowledge into Arabic and Persian. The period is traditionally said to have ended with the collapse of the Abbasid caliphate due to Mongol invasions and the Siege of Baghdad in 1258.

Illustration of The Golden Age of Islam

Who is Harun Al-Rashid?

Harun al-Rashid, whose name translates to, "the Just", "the Upright", or "the Rightly-Guided", was the fifth Abbasid caliph of the Abbasid Caliphate. He was born around 763 or 766 and reigned from September 786 until his death in March 809. His reign is traditionally regarded as the beginning of the Islamic Golden Age.

Harun al-Rashid established the legendary library Bayt al-Hikma (House of Wisdom) in Baghdad, which became a world centre of knowledge, culture, and trade. Scholars from all over the Muslim world flocked to Baghdad to translate the known world's classical knowledge into Arabic and Persian.

During his rule, the family of Barmakids, which played a deciding role in establishing the Abbasid Caliphate, declined gradually. In 796, he moved his court and government to Raqqa in present-day Syria. Domestically, Harun pursued policies similar to those of his father Al-Mahdi. He released many of the Umayyads and 'Alids his brother Al-Hadi had imprisoned and declared amnesty for all political groups of the Quraysh.

Large-scale hostilities broke out with Byzantium, and under his rule, the Abbasid Empire reached its peak. A Frankish mission came to offer Harun friendship in 799. Harun sent various presents with the emissaries on their return to Charlemagne's court, including a clock that Charlemagne and his retinue deemed to be a conjuration because of the sounds it emanated and the tricks it displayed every time an hour ticked.

Portions of the fictional One Thousand and One Nights are set in Harun's court and some of its stories involve Harun himself. Harun's life and court have been the subject of many other tales, both factual and fictitious.

Bayt Al-Hikmah (House of Wisdom)

The House of Wisdom, also known as Bayt al-Ḥikmah in Arabic, was a major public academy and intellectual centre in Baghdad during the Islamic Golden Age. It was one of the world's largest public libraries at the time.

The House of Wisdom was founded either as a library for the collections of the Caliph Harun al-Rashid in the late 8th century or as a private collection created by al-Mansur to house rare books and collections of poetry in Arabic. During the reign of the Caliph al-Ma'mun, it was turned into a public academy and a library.

The House of Wisdom was a part of the major Translation Movement taking place during the Abbasid Era, translating works from Greek and Syriac to Arabic. This translation movement lent momentum to a great deal of original research occurring in the Islamic world, which had access to texts from Greek, Persian, and Indian sources.

The House of Wisdom was made possible by the consistent flow of Arab, Persian, and other scholars of the Islamic world to Baghdad, owing to the city's position as the capital of the Abbasid Caliphate. The fields to which scholars associated with the House of Wisdom contributed include, but are not limited to, philosophy, mathematics, medicine, astronomy, and optics.

The House of Wisdom and its contents were destroyed in the Siege of Baghdad in 1258. Most knowledge about it is derived from the works of contemporary scholars of the era such as al-Tabari and Ibn al-Nadim.

Illustration of the Bayt Al-Hikmah, the world's largest library at the day

Some Muslim Scholars from the Bayt Al-Hikmah

The House of Wisdom in Baghdad was a hub of intellectual activity during the Islamic Golden Age, attracting scholars from various fields and regions. Here are some notable scholars associated with the House of Wisdom:

Banu Musa Brothers: Known for their work in various fields such as mathematics, astronomy, and mechanics.

Al-Khwarizmi: Often referred to as the father of algebra, he made significant contributions to mathematics, astronomy, and geography.

Al-Battani: A renowned astronomer, astrologer, and mathematician.

These scholars, among others, used to meet every day for translation, reading, writing, scribing, discourse, dialogue, and discussion. They played a crucial role in the translation of foreign manuscripts, including those in Persian, Syriac, Greek, and Arabic. This facilitated the transfer of knowledge from various cultures into the Islamic world, contributing to the intellectual richness of the Islamic Golden Age.

Illustration of the Muslim scholars working inside the Bayt Al-Hikmah

Who is Al-Khwarizmi (Algebra)

Abu Abdullah Muhammad ibn Musa al-Khwarizmi, often known as Al-Khwarizmi, was a significant figure in the fields of mathematics and geography during the Islamic Golden Age.

Illustration of Al-Khwarizmi, the father of algebra

Mathematics

Al-Khwarizmi is often referred to as the 'father of algebra'. He was the first to clearly distinguish between algebra and geometry and provided geometrical solutions to equations that were linear or quadratic. His work on elementary algebra, "Al-Kitāb al-mukhtaṣar fī ḥisāb al-jabr waʾl-muqābala" (The Compendious Book on Calculation by Completion and Balancing), introduced the concept of algebra into European mathematics. This book is a compilation of rules, along with demonstrations, for finding solutions of linear and quadratic equations based on intuitive geometric arguments. His systematic, demonstrative approach distinguishes it from earlier treatments of the subject.

Geography

In addition to his works in mathematics, Al-Khwarizmi made important strides in geography. He helped create a world map for al-Mamun and took part in a project to find the Earth's circumference, in which he measured the length of a degree of a meridian in the plain of Sinjar. He also revised and updated one of Ptolemy's books on cartography and geography.

Al-Khwarizmi's contributions to both mathematics and geography have had a lasting impact, influencing these fields for centuries to come.

End of the Abbasid Caliphate and The Golden Age of Islam

The Abbasid Caliphate ended due to a series of events. The decline of Abbasid power began in 945, when the Buyids, a family of tribesmen from northwestern Iran, took control of Baghdad. However, they retained the Abbasid caliphs as figureheads.

The final blow came in 1258 when the Mongols, led by Hulagu Khan, sacked Baghdad. The Mongols destroyed the city, including the great library, the House of Wisdom. The last Abbasid Caliph in Baghdad, Al-Musta'sim, was killed during the Mongol invasion. This marked the end of the Abbasid Caliphate in Baghdad.

However, the Abbasid line continued in Cairo under the Mamluk Sultanate until 1517, but by this time, the Abbasid Caliphs in Cairo were largely ceremonial. The Ottoman Empire, which captured Cairo in 1517, also claimed the title of Caliphate, marking the end of the Abbasid Caliphate.

Illustration of the fall of the Abbasid Caliphate

The bloody Mongol Invasion

The Mongol invasion of Baghdad, also known as the Siege of Baghdad, took place from January 29 to February 10, 1258. It was carried out by Ilkhanate Mongol forces and allied troops.

The Mongols were under the command of Hulagu Khan, the grandson of Genghis Khan. Hulagu Khan had been instructed by the great Khan Möngke to attack Baghdad if the Caliph Al-Musta'sim refused Mongol demands for his continued submission to the khagan and the payment of tribute in the form of military support for Mongol forces in Persia. 

Despite hearing rumours of the Mongols' advance, Caliph Mustasim was confident that the entire Muslim world would rise to defend its ruler if need be. However, the Sunni caliph had recently insulted his Shiite subjects, and his Shiite grand vizier, al-Alkamzi, may have even invited the Mongols to attack the poorly-led caliphate.

The Mongols besieged the city, which surrendered after 12 days. During the next week, the Mongols sacked Baghdad, committing numerous atrocities. The city's walls fell, and the hordes rushed in, collecting mountains of silver, gold, and jewels. Hundreds of thousands of Baghdadis died, slaughtered by Hulagu's troops or their Georgian allies.

Books from the Bayt al-Hikmah, or House of Wisdom, were thrown into the Tigris, supposedly, so many that a horse could have walked across the river on them. The siege marked the end of the Islamic Golden Age.

The Mongols executed Al-Musta'sim and massacred many residents of the city, which was left greatly depopulated. The siege marked the end of the Islamic Golden Age, during which the caliphs had at their peak extended their rule from the Iberian Peninsula to Sindh, and which was also marked by many cultural achievements in diverse fields.

Illustration of the Mongol Invasion of Baghdad

Affections from the Mongol Invasion

The Mongol invasion of Baghdad in 1258 had profound effects on Islamic civilization.

Cultural Impact

The invasion led to the destruction of the House of Wisdom, a major intellectual centre of the Islamic world. Many books, scholars, theories, etc. were lost to the Islamic world. Eyewitnesses reported that the Tigris River ran black with ink from the precious books and documents destroyed along with the Grand Library of Baghdad. This event marked the end of the Islamic Golden Age.

Demographic Impact

Baghdad, which had been a major cultural and economic hub, was left depopulated and in ruins. It's estimated that hundreds of thousands, possibly millions, of citizens of the Abbasid Empire died. Baghdad was a depopulated, ruined city for several decades and only gradually recovered some of its former glory.

Political Impact

The fall of Baghdad fractured Muslim lands into various political dominions. Within a century or two, a new Islamic world order was born, dominated by three competing "gunpowder empires". Some speculate that the Mongol conquests set the stage for Europe to become the dominant power in the ensuing centuries.

In summary, the Mongol invasion of Baghdad had a significant impact on Islamic civilization, leading to cultural loss, demographic changes, and political shifts.

Source: Conversation with Bing, 12/18/2023
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