It continued to be a place of much importance throughout the Abbasid period.

Islamic scholars of the Abbasid period were faced with a huge corpus of miscellaneous traditions, some of them flatly contradicting each other.

The Abbasid historical period lasting to 1258 ( Mongol conquest of Baghdad ) is considered the Islamic Golden Age.

He treats the period as a time of crisis, but not the end of the Abbasid caliphate.

The Abbasid period also coincided with two major innovations in the ceramic arts: the invention of faience, and of metallic lusterware.

Though the common perception of Abbasid artistic production focuses largely on pottery, the greatest development of the Abbasid period was in textiles.

Some of the significant achievements of early Muslim philosophers included the development of a strict science of citation, the isnad or " backing "; the development of a method of open inquiry to disprove claims, the ijtihad, which could be generally applied to many types of questions ( although which to apply it to is an ethical question ); the willingness to both accept and challenge authority within the same process ; recognition that science and philosophy are both subordinate to morality, and that moral choices are prior to any investigation or concern with either ; the separation of theology ( kalam ) and law ( shariah ) during the early Abbasid period, a precursor to secularism ; the distinction between religion and philosophy, marking the beginning of secular thought ; the beginning of a peer review process ; early ideas on evolution ; the beginnings of the scientific method, an important contribution to the philosophy of science ; the introduction of temporal modal logic and inductive logic ; the beginning of social philosophy, including the formulation of theories on social cohesion and social conflict ; the beginning of the philosophy of history ; the development of the philosophical novel and the concepts of empiricism and tabula rasa ; and distinguishing between essence and existence.

In the Islamic world, shipbuilding thrived at Basra and Alexandria, the dhow, felucca, baghlah and the sambuk, became symbols of successful maritime trade around the Indian Ocean ; from the ports of East Africa to Southeast Asia and the ports of Sindh and Hind ( India ) during the Abbasid period.

In the period of the Abbasid caliph Al-Ma ' mun ( 813 – 833 ), the name Oghuz starts to appear in the works of Islamic writers.

Kushks ( Persian, Kushk, " pavilion ", " kiosk "), which comprise the chief remains of Abbasid Merv, are a building type unique to Central Asia during this period.

An Aramaic inscription initially dated to the 6th century, and recently redated to Abbasid or Umayyad period, was found on a kelila ( a type of chandelier ) found in the synagogue.

The late 10th-century Arab geographer al-Muqaddasi noted that during the Abbasid period, Adhri ' at was a major administrative center on the edge of the desert.

After this period of travel, he settled down in the Abbasid capital of Baghdad.

One of the most common forms of literature during the Abbasid period was the compilation.

His education was highly facilitated due to the fact that the Abbasid Caliphate was in a period of cultural, and intellectual revolutions.

According to Rabbi Avraham ben David, in his Sefer HaQabbalah, the Karaite movement crystallized in Baghdad in the Gaonic period ( circa 7th – 9th centuries CE ), under the Abbasid Caliphate in what is present-day Iraq.

The Abbasid historical period lasting to 1258 ( Mongol conquest of Baghdad ) is considered the Islamic Golden Age.

During the period of the Abbasid Caliphate, the office of the qadi al-qudat ( Chief Justice of the Highest Court ) was established.

During the later Umayyad period ( 705 – 750 CE ), a growing class of Muslim legal scholars, distinct from the qadis, busied themselves with the task of supplying the needed body of law, and by the time of the accession to power of the Abbasid dynasty in 750 their work could be said to have been essentially completed.

There are records of the Four Great Caliphs presiding over Nowruz celebrations, and it was adopted as the main royal holiday during the Abbasid period.

Hunayn ibn Ishaq was a Nestorian Christian born in 809, during the Abbasid period, in al-Hira, Iraq.

Unlike other translators in the Abbasid period, Hunayn opposed translating texts word for word.

This arrangement was probably done during the 3rd century of Hijrah during the ' Abbasid period, following the practices of speakers of other Semitic languages such as Aramaic, Hebrew, Syriac and Chaldean.

From 636 until the beginning of the Crusades, Palestine was ruled first by Medinah-based Rashidun Caliphs, then by the Damascus-based Umayyad Caliphate and after that the Baghdad-based Abbasid Caliphs.

According to Imad ad-Din, Nur ad-Din wrote to Saladin in June 1171, telling him to reestablish the Abbasid caliphate in Egypt, which Saladin coordinated two months later after additional encouragement by Najm ad-Din al-Khabushani, the Shafi ' i faqih, who vehemently opposed Shia rule in the country.

Numerous stories depict Jinns, Ghouls, Apes, sorcerers, magicians, and legendary places, which are often intermingled with real people and geography, not always rationally ; common protagonists include the historical Abbasid caliph Harun al-Rashid, his Grand Vizier, Jafar al-Barmaki, and his alleged court poet Abu Nuwas, despite the fact that these figures lived some 200 years after the fall of the Sassanid Empire in which the frame tale of Scheherazade is set.

Still, as political and economic fortune had passed elsewhere, the city went into a rapid decline, especially after the founding of the Abbasid capital at Baghdad in the 8th century, and soon became a ghost town.

It was ruled by the Abbasid dynasty of caliphs, who built their capital in Baghdad after overthrowing the Umayyad caliphate from all but the al-Andalus region.

The 13th century also saw attempts at a Franco-Mongol alliance, with exchange of ambassadors and ( failed ) attempts at military collaboration in the Holy Land during the later Crusades, though eventually the Mongols in the Ilkhanate, after they had destroyed the Abbasid and Ayyubid dynasties, eventually themselves converted to Islam, and signed the 1323 Treaty of Aleppo with the surviving Muslim power, the Egyptian Mamluks.

Al-Mansur was born at the home of the ' Abbasid family after their emigration from the Hejaz in 95 AH ( 714 AD ).

Only after their destruction could the invading Mongols proceed to remove the Abbasid caliph from Baghdad and advance their conquest westward.

In addition to such secular titles, the Ottoman sultan became the Caliph of Islam bearing the title Khalifeh ül-Rasul Rub al-A ’ alimin ( i. e. Successor of the Prophet of the Lord of the Universe ), starting with Selim I, who became Caliph in 1517 after Al-Mutawakkil III, the last of the Abbasid Caliphs in Cairo, formally surrendered the caliphal titles and regalia ( the sword, mantle and other relics of Muhammad ) to Selim in Constantinople the same year.

Mosul had been subjected to a short siege in the autumn of 1182, but after mediation by the Abbasid caliph an-Nasir, Saladin withdrew his forces.

The latter raised an army of 120, 000 and in 1258, sacked Baghdad and slaughtered its inhabitants, including the Abbasid caliph and most of his family after the Ayyubids failed to assemble an army to protect the city.

Even after the foundation of Soltangala by Abu Muslim at the start of the Abbasid dynasty, Gäwürgala persisted as a suburb of the larger Soltangala.

Others, however, have noted that much of the culture of the Maʻdān is in fact shared with the desert bedouin who came to the area after the fall of the Abbasid Caliphate, and that it is therefore likely that they are descended from this source, at least in part.

Over 22, 000 Arab mercenaries were sent by the Abbasid caliph al-Mansur to join the Tang in 756, staying in China after the war.

He knew the personalities of both his sons and decided that for the good of the Abbasid dynasty, Al-Ma ' mun should be caliph after his death, which he confided to a group of his courtiers.

According to Shi ' a accounts, after his father's assassination at the will of Al-Mu ' tasim, the Abbasid caliph ordered Umar bin al-Faraj to find a teacher in Medina for the young Imam that would preach hatred toward the Ahl al-Bayt.

Mansur al-Hallaj ( ; full name ) ( March 26, 922 ) ( Hijri 309 AH ) was a Persian mystic, revolutionary writer and teacher of Sufism, most famous for his poetry, accusation of heresy and for his execution at the orders of the Abbasid Caliph Al-Muqtadir after a long, drawn-out investigation.

The late dating of the mosaic pavement proves that the intervention of the iconoclasts, after 750, is later than previously thought and is associated with Abbasid conservatives.

His brother who succeeded him as the second Abbasid Caliph Abu Jafar al-Mansur ( r. 754-775 AD ) ( A-p ’ uch ’ a-fo ) helped the Chinese Emperor Suzong of Tang after he appealed for help during the An-Shi Rebellion in regaining control of his capital Chang ' an from the treacherous commander, An Lushan, or his successors in the abortive Yan Dynasty.

He would be the last great Abbasid caliph ; after his death the dynasty would fall into a decline.

He would later establish the Seljuq Sultanate after conquering Persia and retaking the Abbasid Capital of Baghdad from the Buyid Dynasty in 1055.

Bilad al-Sham ( Arabic بلاد الشام, the country of Syria ), in English usually referred to as Syria, was a Rashidun, Umayyad and later Abbasid Caliphate province, incorporating former Byzantine territories of the Diocese of the East, organized soon after the Muslim conquest of Syria in the mid-7th century, which was completed at the decisive Battle of Yarmouk.

The Qadariyyah evolved into Mu ‘ tazilah which for some time was the dominant form of kalam, imposed as official orthodoxy under the Abbasid dynasty, until the accession of Al-Mutawakkil in 847, after which it was suppressed.

Abbas rebuilt the site three years later as an Abbasid military colony in preparation for Caliph al-Ma ' mun's planned conquest of Byzantium, but after Ma ' mun's sudden death in August 833 the campaign was abandoned by his successor al-Mu ' tasim and the half-rebuilt city was razed again.