Grumbates or Krumbates was a king of the Chionitae, probably of the Kidarites tribe, an ancient nomadic tribe of Transoxiana.
Etymology
The exact origin of his name is not fully known. Hyun Jin Kim etymologized his name as
*Qurum-pat, "ruling prince";
containing Iranian element
pat "chieftain, ruler"
and
Turkic languages qurum "rule, leadership, administration"
which is attested in the name of Bulgarian khan
Krum.
Attacks on the Sasanian Empire
The Kidarite king Grumbates mentioned by Ammianus Marcellinus was a cause of much concern to the Persians. Between 353 AD and 358 CE, the Xionites under Grumbates attacked in the eastern frontiers of
Shapur II's empire along with other nomad tribes. After a prolonged struggle they were forced to conclude a peace, and their king Grumbates accompanied Shapur II in the war against the Romans.
Alliance with Shapur II against the Romans
Grumbates thus participated in the Siege of Amida in 359 AD as an ally of
Shapur II.
[ Sassanian Iran- economy, society, arts and crafts, N.N.Chegini and A.V. Nikitin, History of Civilizations of Central Asia: The crossroads of civilizations, (UNESCO, 1996), 38.] His participation to the Sasanian campaign in the Eastern Caspian lands are described by Ammianus Marcellinus, who was inside the fortress of Amida at the time:
[History of Civilizations of Central Asia, Ahmad Hasan Dani, B. A. Litvinsky, Unesco p.38 sq]
The son of Grumbates, while inspecting the defences of Amida, was shot and killed with an arrow shot by the city garrison.
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