Below is a video reconstruction of the Battle of Carrhae in 54 BC. In this battle, Iran’s Parthian cavalry led by General Surena defeated the Roman forces of Marcus Lucinius Crassus. Despite outnumbering the Iranians by up to four to one (40,000 Romans and their allies versus 10,000 Iranians), Crassus was defeated and killed.
The Iranian forces led by General Surena were compsoed 1,000 heavy armored knights, supported by up to 9,000 horse archers.
For mor eon this topic, readers are referred to Shadows in the Desert: Ancient Persia at War on pages 131-143.
Reconstruction of Battle of Carrhae-Part 1
Reconstruction of Battle of Carrhae-Part 2
Reconstruction of Battle of Carrhae-Part 3