For some Orthodox Christians, Christmas falls on January 7. The reason for this is that the Eastern Orthodox churches of Russia, Georgia, Ukraine, Macedonia, Montenegro, Serbia and the Greek Patriarchate of Jerusalem observe their feasts in accordance to the more antiquated Julian calendar. December 25 on the Julian calendar corresponds to January 7 on the Gregorian calendar, which is followed internationally. Many other Orthodox Christians, such as the churches of Bulgaria, Greece, Romania, Antioch, Alexandria, Albania, Finland and the Orthodox Church in America, began using the Revised Julian calendar in the early 20th century, which corresponds exactly to the Gregorian calendar.
Take a look at these images from Berlin, Bethlehem, Egypt, London and Los Angeles that show Orthodox Christians celebrating the birth of Jesus Christ in January.