Pax Romana was just over two hundred years, started with Augustus, ended in 180AD, the was the height of the Roman Empire. Pax Romana translates to "Roman Peace" in Latin.
Reasons for sucess
- Augutus reforms of creating a much centralised state, making easier to control such a large empire.
- Cllaudius made made the empire more fairer to non citerzens (including slaves) meaning it was less likly for revolts.
- Adoptive dynasty that ruled most of the second century and later 1st, created a more competant leadership.