I was thinking about what year Jesus would percieve himself as being born, because he couldn't just establish a new calendar at birth.
Then I started to wonder if any calendar was used widely enough to cover many culture's before then. And also how we calculate old dates into "the year ----- B.C." Ancient peoples wouldn't have measured their years counting down to an event they didn't know about.
I'm hoping someone here is an expert and can help clarify some of these!
There are many calendars, but Jesus, who was born in Judea under Roman rule would have used the Julian Calendar which is very similar to the Gregorian Calendar. But as a Jew, he would have used the Jewish Lunar calendar as well, for that is what all Jewish holidays are based on. That is why Hannukah and Passover move around from year to year.
In terms of year numbering, there were multiple things that people counted years from. Usually, the Roman government used either Consular years (names of the 2 consuls from that year) or the emperors regnal year. There was also Indiction but that wasn't started until after Jesus' time. But again, there are other numbering systems that were popular in Judea at the time, including years from the beginning of time, which can be estimated from the Torah and years since the building of the Second Temple. But most people didn't number years, usually only governmental records contained year numbering.
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