The Arch commemorates the victories of Emperor Septimius Severus and his sons, Caracalla and Geta, in the two campaigns waged against the Parthians between the years 194 and 199. Before this the Romans had been in conflict with Parthia for hundreds of years with notable campaigns taking place under the command of various of its leaders including Crassus, Trajan and Hadrian spanning from 52BCE through to the early third century. In the first of these, Crassus led an invading army into Mesopotamia, with catastrophic results; at the Battle of Carrhae, Crassus and his son were defeated and killed by the Parthian army under General Surena. The bulk of Crassus’ force was either killed or captured; of 42,000 men, about half died, a quarter made it back to their base in Syria, and the remainder became prisoners of war. Rome was humiliated by this major defeat, which was made even worse by the fact that the Parthians had captured several Legionary Eagle standards. Such history made Severus’ campaigns and the eventual defeat of Parthia particularly important to Rome and worthy of memorialization. The arch has four carved panels that describe, in chronological sequence, the major events in the course of Severus’ campaigns. Unfortunately some of these are in a poor state of preservation and many scenes are barely discernible. The side that faces the forum is particularly damaged because it has always been exposed to the wind and a fire in the Middle Ages. If, as we work our way around the monument, you’re having trouble making out the panel details, bear in mind that clearer modern versions of these reliefs can be seen in the Museo Nazionale della Civiltà Romana.