The Roman republican calendar and the Julian calendar both recognized January 1 as the beginning of the New Year. The date was chosen partly in honor of Janus, the Roman god of beginnings and the month’s namesake. Though medieval Christians attempted to replace January 1 with more religiously significant dates, Pope Gregory XIII created a revised calendar that officially established January 1 as New Year’s Day in 1582. That date was gradually adopted in Europe and beyond; it subsequently spread to countries without dominant Christian traditions.