When does the Gregorian Calender has anything to do with religion. Its a common calender that almost all of the world abides by. The Gregorian Calender is based on the Earth going around the Sun which takes around 365 days where as the Lunar Calender that Muslims and few other religion go by is the time the moon takes to orbit the earth.

So lets celebrate start of a new year without getting too much into the debate who is right and who wrong.