The Parthian Empire at its Greatest Extent (c. 96 BC)
In the early 1st century BC, Parthia’s territory expanded to the River Euphrates. Parthian and Roman envoys met to establish this landmark as the boundary between the two superpowers. At this first meeting, the Roman magistrate reportedly seized the seat of honour, humiliating his Parthian counterpart as the inferior ambassador. In 53 BC, Parthia finally demonstrated its strength by crushing the Roman army at Carrhae. 30,000 soldiers were killed or captured, and several legionary standards were lost to the Parthians.
Alexandra Magub - School of Oriental and African Studies and The British Museum