The main Church of Serbia and Montenegro is the Orthodox Church. Like Russia, the tradition is to use the Julian calendar as opposed to the modern Gregorian calendar - at least when it comes to holidays and traditions. Day to day life is ruled by the Gregorian calendar.
Serbia culture is a historically eventful because of the invasion of different nations at different points of time. Yet, in spite of the multicultural influence, the Balkan natives of Serbia have sustained their own culture and tradition while adopting to many new ways of life and various customs.
Belgrade - Serbian partygoers and caterers happily exploit an atavistic calendar to celebrate New Year's parties on December 31 and January 13, with an Orthodox Christmas in between.