The Tayy were subjects of the Sassanid Persians. However, they were also counted as allies by the Byzantines' chief Arab "foederati" in the early to mid-5th century, the Salihids. The Tayy are mentioned in the late 5th century as having raided numerous villages in the plains and mountains of the Syrian Desert, including parts of Byzantine territory. This prompted the Byzantine army to mobilize its Arab clients at the desert frontiers with Sassanid-held Mesopotamia to confront the Tayy. The Byzantines demanded restitution from the Tayy, but the Sassanid general Qardag Nakoragan instead opened negotiations that called for the Byzantines' Arab clients to restore livestock and captives taken from Sassanid territory in previous years in return for compensation from the Tayy. The negotiations succeeded, and moreover, the Sassanids and Byzantines delineated their borders to prevent future raiding between their respective Arab clients. However, to the embarrassment of the Sassanids and the outrage of the Byzantines, four hundred Tayyid tribesmen raided several minor villages in Byzantine territory while representatives of the two sides were meeting in Nisibis. Despite this violation of the bilateral agreement, the Sassanid-Byzantine peace held.