January 1 is the first day of the calendar year in both the Julian and Gregorian calendars. Here a calendar year refers to the order in which the months are displayed, January to December. The first day of the medieval Julian year was usually a day other than January 1. This day was adopted as the first day of the Julian year by some European countries between 1522 and 1579 (that is, before the creation of the Gregorian calendar in 1582). See beginning of the year. The British Empire (including its American colonies) did not adopt the Gregorian calendar until 1752.