In August of 14 his adoptive grandfather Augustus died. In his honor, Drusus read a eulogy before the rostra at his funeral. The next month, on 17 September, the senate met to confirm his father as "princeps". Among his first acts as emperor, Tiberius instituted the "Sodales Augustales", a priesthood of the cult of Augustus which members of the imperial family, such as Drusus, joined. This wasn't his first religious post though, as he had been a "pontifex" since AD 7/8 - an important step to the prestigious "pontifex maximus". Since 14 May AD 14, he was a member of the "Fratres Arvales" as well.