The Banu Kalb (Arabic: بنو كلب) was an Arab tribe which mainly dwelt in the desert between northwestern Arabia and central Syria. The Kalb was involved in the tribal politics of the eastern frontiers of the Byzantine Empire, possibly as early as the 4th century. By the 6th century, the Kalb had largely adopted Christianity and came under the authority of the Ghassanids, the chief Arab federates of the Byzantines.