The Banu Taghlib (بنو تغلب), also known as Taghlib ibn Wa'il, were an Arab tribe that originated in Jazira. Their parent tribe was the Rabi'a, and they thus traced their descent to the Adnanites. The Taghlib were among the most powerful and cohesive nomadic tribes of the pre-Islamic era and were known for their bitter wars with their kinsmen from the Banu Bakr, as well as their struggles with the Lakhmid kings of al-Hira in Iraq (Lower Mesopotamia). The tribe embraced Miaphysite Christianity and remained largely Christian long after the advent of Islam in the mid-7th century. After early opposition to the Muslims, the Taghlib eventually secured for themselves an important place in Umayyad politics. They allied with the Umayyads and engaged in numerous battles with the rebellious Qaysi tribes during the Qays–Yaman feuding in the late 7th century.
During Abbasid rule, some individuals from the tribe embraced Islam and were given governorships in parts of the Caliphate. By the mid-9th century, much of the Taghlib converted to Islam, partly as a result of the persuasion of the Taghlibi governor of Diyar Rabi'a and founder of al-Rahba, Malik ibn Tawk. Several Taghlibi tribesmen were appointed governors of Diyar Rabi'a and Mosul by the Abbasids. In the early 10th century, a Taghlibi family, the Hamdanids, secured the governorships of these regions, and in the 930s, the Hamdanid leader Nasir al-Dawla formed an autonomous emirate out of Mosul and the Jazira. Likewise, in 945, his brother, Sayf al-Dawla, created a northern Syrian emirate based in Aleppo. The Hamdanids ruled both of these emirates until their political demise in 1002. The Taghlib as a tribe, however, had disappeared from the historical record during the early Hamdanid period.
The Banu Taghlib were originally a Bedouin (nomadic Arab) tribe that inhabited the Najd. The tribe was named after its progenitor Taghlib ibn Wa'il, also known as Dithar ibn Wa'il. The tribe belonged to the Rabi'a confederation and thus traced its descent to the Nizar branch of the Adnanites.