The New Year ‘s classic greeting is “Akemashite Omedetou GozaimasuοΌγγγΎγγ¦γγγ§γ¨γγγγγΎγοΌ”. In English it is translated as “A happy new year”, but if literal translation it is nuance like “Congraturationsm, because the year has come”.
In the past when Japan was not rich, people’s lives were not easy and the average life expectancy was short, so our ancestors celebrated that the New Year was came.
By the way, the New Year in 1989 was silenced by the TV program on the word “congratulations”, because the former emperor was fighting ill.