January 2025 Calendar Wallpaper Hd Download. Download my matching january 2025 wallpapers for your desktop, laptop, tablet and mobile phone devices & sign up for new ones each month! You can also upload and share your favorite calendar 2025 wallpapers.

New year’s day january 4: The gregorian calendar was introduced into use by pope gregory xiii, the leader of the roman catholic church, in 1582.it is based on the solar dating system that reformed the julian calendar, which had been established by the roman emperor julius caesar in 45 bc.