The Economic Times

What is Orthodox Christmas? Why do 250 million people celebrate Christmas on January 7, is it a holiday

Every year, for millions of Christians worldwide, Christmas falls on January 7 rather than December 25. The difference exists because these communities, which includes Russian, Serbian, Coptic, Ethiopian, and Eritrean Orthodox churches, continue to follow the Julian calendar, which is 13 days behind the Gregorian calendar used by most nations.