Caracalla (198 - April 8, 217CE). Marcus Aurelius Severus Antoninus Augustus, the eldest son of Septimius Severus and Julia Domna, was given the rank of Caesar in 196 and created Augustus in 198 although only 10 years old. He ruled jointly with his brother, Geta, upon the death of his father in 211, but had him assassinated in 212. Geta died in his mother's arms. His reign was marked by cruelty, massacres and persecutions. His one notable act, that of granting Roman citizenship to all free inhabitants throughout the empire (Constitutio Antoniniana), was probably initiated with the purpose of increasing tax revenue. He was finally assassinated while urinating on April 8, 217, on orders of the Praetorian Prefect Macrinus. His nickname, Caracalla, is derived from the long hooded Gallic tunic which was his favorite dress. He devalued the Roman coinage by reducing the purity of the denarius and introducing the underweight antoninianus (double denarius) in the latter part of 214.