Slavery in the Abbasid Caliphate in the context of Dar al-islam

The Zanj Rebellion (Arabic: ثورة الزنج Thawrat al-Zanj / Zinj) was a major revolt against the Abbasid Caliphate, which took place from 869 until 883. Begun near the city of Basra in present-day southern Iraq and led by one Ali ibn Muhammad, the insurrection involved both enslaved and freed Africans (collectively termed "Zanj" in this case) exported in the Indian Ocean slave trade and transported to slavery in the Abbasid Caliphate in the Middle East, principally to drain the region's salt marshes. It grew to involve slaves and freemen, including both Eastern Africans and Arabs, from several regions of the Caliphate, and claimed tens of thousands of lives before it was fully defeated.

Several Muslim historians, such as al-Tabari and al-Mas'udi, consider the Zanj revolt to be one of the "most vicious and brutal uprisings" of the many disturbances that plagued the Abbasid central government. Modern scholars have characterized the conflict as being "one of the bloodiest and most destructive rebellions which the history of Western Asia records," while at the same time praising its coverage as being among the "most fully and extensively described campaign[s] in the whole of early Islamic historical writing." The precise composition of the rebels remains a subject of debate, both as regards their identity and as to the proportion of slaves and free among them – available historical sources being open to various interpretations.

The Bukhara slave trade refers to the historical slave trade conducted in the city of Bukhara in Central Asia (present-day Uzbekistan) from antiquity until the 19th century. Bukhara and nearby Khiva were known as the major centers of slave trade in Central Asia for centuries until the completion of the Russian conquest of Central Asia in the late 19th century.

The city of Bukhara was an important trade center along the ancient Silk Road, through which slaves were traded between Europe and Asia. In the Middle Ages, Bukhara came to lie in the religious border zone between the Muslim and non-Muslim world, which was seen as a legitimate target of slavery by Muslims, and referred to as the "Eastern Dome of Islam". It became the center of the massive slave trade of the Samanid Empire, who bought saqaliba (European) slaves from the Kievan Rus' and sold them on to the Middle East, and as such constituted one of the main trade routes of saqaliba slaves to the Muslim world. The conquests and plundering of the Ghaznavid Empire brought a large number of slaves from India into the markets of Bukhara in the 10th and 11th centuries. Bukhara was also a center for the trade of non-Muslim Turkic slaves from Central Asia to the Middle East and India, where they composed the main ethnicity of ghilman (military slaves) for centuries.

The siege of Amorium by the Abbasid Caliphate in mid-August 838 was one of the major events in the long history of the Arab–Byzantine Wars. The Abbasid campaign was led personally by the Caliph al-Mu'tasim (r. 833–842), in retaliation to a virtually unopposed expedition launched by the Byzantine emperor Theophilos (r. 829–842) into the Caliphate's borderlands the previous year. Mu'tasim targeted Amorium, an Eastern Roman city in western Asia Minor, because it was the birthplace of the ruling Byzantine dynasty and, at the time, one of Byzantium's largest and most important cities. The caliph gathered an exceptionally large army, which he divided in two parts, which invaded from the northeast and the south. The northeastern army defeated the Byzantine forces under Theophilos at Anzen, allowing the Abbasids to penetrate deep into Byzantine Asia Minor and converge upon Ancyra, which they found abandoned. After sacking the city, they turned south to Amorium, where they arrived on 1 August. Faced with intrigues at Constantinople and the rebellion of the large Khurramite contingent of his army, Theophilos was unable to aid the city.

Amorium was strongly fortified and garrisoned, but a local inhabitant revealed a weak spot in the wall, where the Abbasids concentrated their attack, effecting a breach. Unable to break through the besieging army, Boiditzes, the commander of the breached section, privately attempted to negotiate with the Caliph without notifying his superiors. He concluded a local truce and left his post, which allowed the Arabs to take advantage, enter the city, and capture it. Amorium was systematically destroyed, never to recover its former prosperity. Many of its inhabitants were slaughtered, and the remainder driven off as slaves. Most of the survivors were released after a truce in 841, but prominent officials were taken to the caliph's capital of Samarra and executed years later after refusing to convert to Islam, becoming known as the 42 Martyrs of Amorium.