 Sources often considered more credible than the Augustan History include the contemporary historians Cassius Dio and Herodian . Cassius Dio lived from the second half of the 2nd century until sometime after 229 . Born into a patrician family , he spent the greater part of his life in public service . He was a senator under emperor Commodus and governor of Smyrna after the death of Septimius Severus . Afterwards he served as suffect consul around 205 , and as proconsul in Africa and Pannonia . 
