Christmas is a widely celebrated holiday that is observed by many countries and cultures around the world. While December 25th is the traditional date of Christmas, many countries have their own unique ways of celebrating it. Some countries, like Russia, celebrate Christmas on January 7th, according to the Julian calendar. This is because Russia uses a different calendar than most other countries, and they celebrate Christmas on the date that aligns with the birth of Jesus according to their calendar. Other countries, like Ethiopia, also have different dates for Christmas, as their calendar is based on a different system.