Answer
The "Res gestae" is a record of the deeds of Roman emperors, written by their successors. It began with the accession of Nerva, the first of the five "good emperors" who ruled Rome from 96 to 180 AD. Nerva's successor, Trajan, continued the tradition of recording his deeds in the "Res gestae", and it was later continued by Hadrian, Antoninus Pius, and Marcus Aurelius.