Wikipedia
Banu Taghlib or Taghlib ibn Wa'il was an Arabian tribe of Mesopotamia and eastern Arabia .The tribe traces its lineage to the large branch of North Arabian tribes ( Adnanites) known as Rabi'ah, which also included Banu Bakr and Abdul Qais in eastern Arabia.
The tribe's ancestral homelands were the region of Nejd, in central Arabia, before migrating northwards to the Jazirah plain in northern Mesopotamia in the 6th century. At that time, the tribe was known to be mostly Christian, and was renowned for its size and strength relative to other tribes. It was even said by the classical Arab genealogists that "had it not been for Islam, Taghlib would have devoured the Arabs." The tribe is also said to have engaged in a 40-year war immediately prior to Islam with the closely related tribe of Banu Bakr, which became known as the War of Basous. Taghlib's migration to Mesopotamia is attributed to this war. During this era, according to classical Arab sources, the tribe produced a poet by the name of 'Amr ibn Kulthum, to whom is attributed one of the highly regarded Seven Hanged Poems of pre-Islamic Arabia. With its bombastic and vainglorious verses on the glories of his tribe, Ibn Kulthum's ode became the prime example of Arabian hyperbole. The tribe, however, soon came into conflict with the Lakhmid rulers of southern Iraq and moved further north to the Jazirah region around the northern reaches of the Euphrates.
Taghlib was one of the few Arab tribes that did not accept Islam during Muhammad's time nor during the rule of his immediate successors. After Muhammad's death, some sections of Taghlib joined in the Ridda Wars ("Wars of the Apostasy"), supporting the claimed prophecy of a woman from Banu Tamim named Sajah. Upon the suppression of the apostasy, Taghlib is said to have reached an agreement to remain Christian in exchange for paying a levy to the reigning caliph. According to this narration, Taghlib, requested that the levy be termed a sadaka (" alms"), similar to what was collected from Muslim tribes, in lieu of the jizya (" tribute" or " poll tax") that was normally taken from non- Muslims. The caliphs agreed.
The Taghlib tribes in lower Iraq anchored the see of their faith at Antioch and, like the Syrian Orthodox and Byzantine-rite patriarchates, refused to surrender to the dictates of Constantinople.
During the Umayyad era, the most famous member of Taghlib was the Christian poet Al-Akhtal, who is still regarded as one of the finest Arab poets of the classical era, and who composed odes in the finest bedouin tradition. He was a close companion of the caliph Yazid I among others.
During the era of the Abbasid dynasty, who replaced the Umayyads in 750, many sections of the tribe began to convert to Islam in the hope of obtaining more political power within the Muslim realm. The Hamdanid dynasty that ruled northern Iraq and Syria in the 10th century claimed descent from Taghlib.