Secundus is first mentioned in the letters of Pope Gregory I for January 596, at which time Secundus served archbishop Marinianus of then-Byzantine Ravenna as deacon.
[1] In that capacity the Pope wrote to Secundus for diplomatic relations between the Lombard king Agilulf (590–616) and the Exarch.
[2] Around 600, Secundus became an abbot and moved to Agilulf's court, where Gregory corresponded with him in 603.
[3] Secundus was godfather to prince Adaloald around that year.
"[5] Paul the Deacon used the work for his Historia Langobardorum, especially concerning Trent and Agilulf's court.