Periodization and time-reckoning
Periodization and time-reckoning: Scholars divide the long history of the Villa of Horace into four periods:
The adjectival form of the word "empire" is "imperial," so throughout this Web site, when we date events or objects to Horace's lifetime, we might say that they belong to "the Horatian period," to "the Augustan age," or to "the Early Imperial period." The dates and divisions given here are somewhat arbitrary, but this is inevitable in any periodization. The purpose of periodization is to give students and scholars convenient approximations, which are used faute de mieux when precise dating is impossible or unnecessary.
As for time-reckoning, it should go without saying that "B.C." means "Before Christ," whereas "A.D." means "Anno Domini" (i.e., "in the year of our Lord"). Since dates given in terms of B.C. and A.D. might be taken to imply belief in Christianity or at least a privileged role for Jesus Christ in human time-reckoning, many scholars around the world today prefer to use the "common era" system of dating, in which the years are the same but you put B.C.E. (i.e., "before the common era") for B.C. dates, and C.E. (i.e., "common era") for A.D. dates. The Romans themselves reckoned time very differently according to years "from the founding of the city" (ab urbe condita, abbreviated as a.u.c.). The canonical foundation date was April 21, 753 B.C., so Horace would have thought of himself as living in about the year 720 a.u.c. when he became the owner of his Sabine villa.