Before the system of B.C. (Before Christ) and A.D. (Anno Domini) was widely adopted, time was recorded in various ways, often tied to specific events, rulers, or even religious calendars. Different cultures and regions used different methods, making it difficult to have a universally consistent way of dating events. Here's a more detailed look at how time was recorded before the widespread use of B.C./A.D.:

1. Regnal Years: Many cultures, including ancient Egypt and Rome, used regnal years, counting years from the start of a ruler's reign. For example, an event might be dated as "the 5th year of Pharaoh Akhenaten's reign".
2. Founding of Cities: The Romans, for instance, counted years from the founding of Rome, using the expression "Ab Urbe Condita" (From the founding of the city), according to a Reddit post.
3. Religious Calendars: Religious calendars, such as the Hebrew calendar, also existed and were used for timekeeping. The Jewish calendar, for example, counted years from the alleged creation of the world.
4. Julian Calendar: The Julian calendar, adopted by the Romans, was also used to keep track of time.
5. Astronomical Observations: Observations of the sun, moon, and stars were also used to determine time and create calendars.
6. Indiction System: The Byzantine calendar used the Indiction system, which was a 15-year cycle used for taxation and other administrative purposes. In Summary: Before the widespread adoption of B.C./A.D., timekeeping varied significantly across cultures and regions. Common practices included regnal years, counting from the founding of a city, using religious calendars, the Julian calendar, and astronomical observations. These methods laid the foundation for the more standardized systems we use today.