This article discusses the turbulent political and military background of the Pax Augusta, which was hailed by imperial propagandists like Vergil in his Aeneiad. The emperor instigated an ambitious architectural programme which included the construction of a monumental sun-dial, equipped with an Egyptian obelisk and freighted with ideological symbolism. The author also correlates Augustus grandiose building projects to his confirmation of Julius Caesar’s calendar reform and the introduction of the seven-day week (hebdomas), which is still in use today.