Siege of Amida (359)

Siege of Amida
Part of the Perso-Roman wars of 337–361
The walls of Amida, built by Constantius II before the siege of 359
Date 359 Location Amida, Mesopotamia (modern-day Diyarbakır, Turkey) 37°55′N 40°13′E / 37.917°N 40.217°E / 37.917; 40.217 Result Sasanian victory[1] Withdrawal of the Persian allies Territorial changes Sasanian forces capture Amida
Belligerents
Sasanian Empire and allies	Eastern Roman Empire
Commanders and leaders
Shapur II or Peroz Tamshapur Grumbates Urnayr	Aelianus [2] Sabinianus Ursicinus
Units involved
Sassanian army Xionites Gelani Albani Segestani	Legio V Parthica and an unnamed cavalry unit (garrison) Legio XXX Ulpia A detachment of Legio X Fretensis Tricensimani Decimani Superventores and Praeventores (light cavalry) Comites Sagittarii (Household mounted archers) Magnentiaci and Decentiaci (legions from Gaul loyal to Magnentius)
Strength
c. 100,000[3]	20,000-120,000[4][5] est. 5,300 soldiers[3]
Casualties and losses
circa 30,000 dead[6]	Most defenders, some citizens, some refugees from countryside[7]
Amida class=notpageimage| Location of the Siege of Amida Show map of West and Central Asia Amida Amida (Turkey) Show map of Turkey

The siege of Amida was a military investment of the Roman fortified frontier city of Amida (modern Diyarbakır, Turkey) by the Sasanian Empire. It took place in AD 359 when the Sasanian army under king Shapur II invaded the eastern provinces of the Roman Empire. Shapur wanted to exploit the absence of the Roman Emperor Constantius II who was overseeing affairs in the western part of the Empire. The city fell, but the strategic gain was little.

Ammianus Marcellinus, a Roman army officer, provided a vivid description of the siege in his work (Res Gestae). Ammianus served on the staff of Ursicinus, the Magister Equitum (master of horse) of the East, during the events of the siege.^[8]