Where did celebrating New Year's Eve originate?

Answer

The custom of celebrating old years or new years eve has something to do with the Pagan god Janus (who also is the reason for the name January). Janus was a two-headed deity (or god) who had one head looking at the past (meaning the old year) and the other head looking towards the future (the new year). New years celebrations originated from the worship of Janus.