The Arcus Argentariorum was built in 204 by the Guild of Money-Changers in honour of the emperor Septimius Severus (r. 193-211), his wife Julia Domna, and their children Geta and Caracalla.
Bas-relief of Emperor Septimius Severus & Julia Domna
Both the emperor and empress appear on the inside of the arch making an offering. The images of Geta and Caracalla originally adorned the opposite side, but that of Geta was erased following his assassination at the behest of his brother.
After the death of Septimius Severus on February 4th 211, the brothers ruled jointly as co-emperors. However, on December 22nd 211, Geta was killed by soldiers on the instruction of his older brother Caracalla. Geta was twenty-two years old.
Caracalla ruled as sole emperor until April 8th 217, when he in turn was assassinated. He had just turned twenty-nine.