Gregorian calendar It also specifies its epact relative to 1 January, in contrast with the Julian calendar, which specified it relative to 22 March. The old date was derived from the Greek system: the earlier "Supputatio Romana" specified it relative to 1 January. During the period between 1582, when the first countries adopted the Gregorian calendar, and 1923, when the last European country adopted it, it was often necessary to indicate the date of some event in both the Julian calendar and in the Gregorian calendar, for example, "10/21 February 1750/51", where the dual year accounts for some countries already beginning their
Adoption of the Gregorian calendar public, however, resisted the change and continued to observe traditional holidays. President Yuan Shikai switched to a dual-calendar policy, under which the Gregorian calendar was to be used for most purposes except traditional holidays, which were to be timed according to the Chinese calendar, including the short-lived Empire of China. When the communists took over China in the late 1940s they kept this two-calendar system for the People's Republic of China. Today mainland China (including Hong Kong and Macau), Taiwan, Malaysia, Indonesia and Singapore all observe traditional holidays based on the traditional calendar, such as Lunar New Year, while timing