1 January

1 January (the First of January, January 1st, &c.) is the first day of the year under the Gregorian calendar, as first promulgated by Pope Gregory XIII, Bishop of Rome, in 1582 A.D., as well as the earlier Julian calendar, as first promulgated by Julius Caesar in 45 B.C. The date of 1 January is followed by either 364 days or 365 days during leap years, which are calculated differently in Gregorian and Julian calendars; in both calendars, regardless of its leap year status, the date that follows is 2 January and the date that precedes it is 31 December. Many cultures that use these calendars in their accounting for the partitioning of time along solar lines mark the date of 1 January as New Year's Day, a celebratory festival of the new year.

Note that for the purposes of the following indices, the Gregorian date trumps the Julian date, unless otherwise indicated.

Births

• Arthur Posnansky (1873-1946), adventurer and jack-of-all-trades
• Ralph Herrick (1922-2013), co-discoverer of the jackelope
• Alexander Abian (1923-1999), mathematician and proponent of destroying the Moon

Deaths

• Ignatius Donnelly (1831-1901), U.S. politician and lawyer
• Paul Alfred Müller (1901-1970), pulp author
• Simão Toco (1918-1984), Mukongo religious leader, founder of the Tocoista Church
• Leon Davidson (1922-2007), engineer and scientific ufologist
• Fred Keziah (1920-2010), cartoonist and animator