Talbert calls for the application of comparative history and social psychology to Romans’ preoccupation with knowing the hour by day and by night. This has been overlooked as a distinctively Roman habit, one long predating the emergence of such concern in 14/15th century Europe. The lecture divides into four sections. First, a demonstration – exploiting evidence from inscriptions especially – that the habit cannot be restricted to the elite, or to urban contexts, or to just one or two of the twelve hours; nor is it an obstacle that these are seasonal hours of varying length. Second, brief comparison with the limited attention paid to knowing the hour in earlier or contemporary societies of the Near East, Egypt and Greece. Third, consideration of possible means by which attention to knowing the hour reached Rome, as well as how, when and why such awareness spread throughout the Roman world and persisted for centuries. Fourth, comparison of Roman and pre-modern Japanese attention to seasonal hours.