 Rome's forces, under Emperor Alexander split up into three columns, one which went to Armenia (the left column), one which went to the Euphrates (the right column), and one that stayed in Mesopotamia, led by the emperor himself.Ardashir engaged the right column in battle, defeated it, and on this note, Alexander decided to end the war and retreated, although a peace treaty was never signed.In 233, after winning his wars in the east, Ardashir again invaded Rome, this time captured Nisibis and Carrhae.