Originally procurator of Gallia Belgica, Suburanus was appointed prefect of the Roman imperial bodyguard, known as the Praetorian Guard, in the year 98 and brought this important military unit under Trajan's control.
[1] For his achievement, at the end of his command of the Guard, Suburanus was adlected into the Roman senate inter praetores, then held the suffect consulship as the colleague of the consul posterior Quintus Articuleius Paetus in AD 101.
Next he was prefectus of the ala Taurina, a cohort of auxiliary cavalry; Tacitus mentions this unit as present at Lugudunum with the Legio I Italica in early spring AD 69.
The last was a vitally important office, for this procurator handled the finances for the legions on the Rhine frontier, one of the largest groups of soldiers in the Roman Empire.
In the opinion of the historian John D. Grainger, the manner in which Casperius was dispatched left the rest of the men in the Praetorian Guard "surely very resentful at the execution of their officers and colleagues and at the deceitful way it had been accomplished.