Gaius[1] Cassius Regallianus[2] was a Roman senator active around AD 200.
This discovery, and especially Regallianus' existence, attracted attention, for previously the only known occurrence of the cognomen "Regal(l)ianus" is that of a usurper, Regalianus, who in 260 revolted against the emperor Gallienus, in the area of the Danube.
The coins minted from the usurper bear his name as P C REGALIANVS, whose nomen is usually expanded as Cornelius, although other possibilities are not excluded.
The presence, in the early 3rd century, of a consul with the rare cognomen Regalianus and belonging to a family whose name begins with 'C' opens the way to some interesting possibilities.
A Regalianus descended from this consul might have been appointed governor of Moesia or Pannonia, and have rebelled against Gallienus.