"For the magister officiorum under Constantius II, see Decentius (magister officiorum).
Magnus Decentius (died 18 August 353) was a usurper of the western portion of the Roman Empire against emperor Constantius II. Decentius was the brother of Magnentius, who had revolted against Constantius on 18 January 350." - (en.wikipedia.org 11.08.2021)
