Wikipedia
The Jarrahids (also known as Banu al-Jarrah) were an Arab dynasty that intermittently ruled Palestine and controlled Transjordan and northern Arabia in the late 10th and early 11th centuries. They were described by historian Marius Canard as a significant player in the Byzantine–Fatimid wars in Syria who "created for themselves, in their own best interests, a rule of duplicity, treason and pillage". They were the ruling family of the Tayy tribe, one of the three powerful tribes of Syria at the time; the other two were Kalb and Kilab.
The Jarrahids first emerged in the Muslim sources as allies of the Qarmatians, and grew prominent under their chieftain Mufarrij ibn Daghfal ibn al-Jarrah. In 973, the latter secured the governorship of Palestine, with Ramla at its center, from the Fatimid Caliphate in reward for military services. Mufarrij lost favor with the Fatimids, who drove the Jarrahids out of Palestine when they plundered Ramla in 981. Afterward, the Jarrahids raided Mecca-bound Hajj pilgrim caravans and vacillated between the Fatimids, Byzantines and individual Muslim rulers in Syria. By 1011–12, the Jarrahids controlled all of interior Palestine up to Tiberias and defied the Fatimids by declaring their own caliph, al-Hasan ibn Ja'far, at Ramla. The Fatimid caliph al-Hakim then paid Mufarrij to end the rebellion, but not long after dispatched an expedition against the Jarrahids in which they were driven from Palestine.
Mufarrij died in 1013 and was succeeded by his son Hassan, who regained control of Palestine. He entered the Tayy into an alliance with Kalb and Kilab, which dominated Syria until its defeat by the Fatimids in 1029. As a result, the Jarrahids moved their encampments close to their Byzantine allies near Antioch. They fought alongside the Byzantines in several confrontations with regional Muslim powers. After 1041, there were only scattered mentions of the Jarrahids, namely regarding Hassan's nephews, Hazim ibn Ali and Humayd ibn Mahmud in the 1060s, and Hazim's grandson, Fadl ibn Rabi'ah, who at times was an ally of the Fatimids, Crusaders, Mazyadids or the Seljuks. He became the progenitor of the Al Fadl dynasty whose emirs came to dominate the Bedouin of the Syrian Desert and steppe until the 18th century.