45 BC – The Julian calendar takes effect as the civil calendar of the Roman Republic, establishing January 1 as the new date of the new year.
404 – Saint Telemachus tries to stop a gladiatorial fight in a Roman amphitheatre, and is stoned to death by the crowd. This act impresses the Christian Emperor Honorius, who issues a historic ban on gladiatorial fights.
1502 – The present-day location of Rio de Janeiro, Brazil, is first explored by the Portuguese.[12]
1700 – Russia begins using the Anno Domini era instead of the Anno Mundi era of the Byzantine Empire.
1773 – The hymn that becomes known as “Amazing Grace”, previously titled “1 Chronicles 17:16–17, Faith’s Review and Expectation”, is first used to accompany a sermon led by John Newton in the town of Olney, Buckinghamshire, England.
1776 – During the Revolutionary War, Norfolk, Virginia, is burned to the ground by combined Royal Navy and Continental Army action.
– General George Washington hoists the first United States flag, the Continental Union Flag, at Prospect Hill.
1781 During the Revolutionary War, 1500 soldiers of the 6th Pennsylvania Regiment under General Anthony Wayne’s command rebel against the Continental Army’s winter camp in Morristown, New Jersey in the Pennsylvania Line Mutiny.
1801 – Ceres, the largest and first known object in the Asteroid belt, is discovered by Giuseppe Piazzi.[31]
1808 – The Act Prohibiting Importation of Slaves of 1807, 2 Stat. 426 Pub. L. 9–22 comes into effect, banning the importation of slaves into the U.S.
1818 – Mary Shelley anonymously publishes the pioneering work of science fiction The Modern Prometheus, commonly known as , Frankenstein in London.
1847 – The Sisters of Mercy from Ireland, found the “Mercy” Hospital Pittsburgh
1863 – During the War between the states, the Emancipation Proclamation takes effect in Confederate states.
1885 – Twenty-five nations adopt Sandford Fleming’s proposal for standard time (and also, time zones).[45]
1892 – Ellis Island begins processing immigrants into the United States.
1898 – New York, New York annexes land from surrounding counties, creating the City of Greater New York. The four initial boroughs, Manhattan, Brooklyn, Queens, and The Bronx, are joined on January 25 by Staten Island to create the modern city of five boroughs.
1902 – The first American college football bowl game, the Rose Bowl between Michigan and Stanford, is held in Pasadena, California.
1914 – The St. Petersburg–Tampa (SPT) Airboat Line becomes the world’s first scheduled airline to use a winged aircraft. Providing service provided service between St. Petersburg, Florida and neighboring Tampa across Tampa Bay
1932 – The United States Post Office Department issues a set of 12 stamps commemorating the 200th anniversary of George Washington’s birth.
1942 – The Declaration by United Nations is signed by twenty-six nations.
1947 – The American and British occupation zones in Allied-occupied Germany, after World War II, merge to form the Bizone, which later (with the French zone) became part of West Germany.
1958 – The European Economic Community is established.[72]
1959 –The government of Cuba, under Fulgencio Batista, is overthrown by Fidel Castro’s forces.
1970 – The defined beginning of Unix time starts, at 00:00:00.
1971 – Cigarette advertisements are banned on American television.
1979 – The Joint Communiqué on the Establishment of Diplomatic Relations and Taiwan Relations Act enter into force. Through the Communiqué, the United States establishes normal diplomatic relations with China and guarantees military support for Taiwan.
1983 – The ARPANET officially changes to using TCP/IP, the Internet Protocol, effectively creating the Internet.
1984 – The original American Telephone & Telegraph Company is divested of its 22 Bell System companies as a result of the settlement of the 1974 United States Department of Justice antitrust suit against AT&T.
1985 – Eastern Air Lines Flight 980, a Boeing 727, on a scheduled international flight from Asunción, Paraguay, to Miami, Florida, while descending towards La Paz, Bolivia, for a scheduled stopover, crashes into Mount Illimani, killing all 29 people on board.
1988 – The Evangelical Lutheran Church in America is formed, creating the largest Lutheran denomination in the United States.
1989 – The Montreal Protocol comes into force, stopping the use of chemicals contributing to ozone depletion in the atmosphere.
1993 – By mutual accord, Czechoslovakia is divided into the Czech Republic and Slovak Republic.
1994 – The North American Free Trade Agreement (NAFTA) comes into effect.
1995 – The World Trade Organization comes into being.
1998 – Argentinian physicist Juan Maldacena publishes a landmark paper initiating the study of AdS/CFT (anti-de Sitter/conformal field theory) correspondence, which links string theory and quantum gravity.
1999 – The Euro currency is introduced in 11 member nations of the European Union.
2011 – A bomb explodes as Coptic Christians in Alexandria, Egypt, leave a new year service, killing 23 people.
2024 – A 7.5 Mww earthquake strikes the western coast of Japan, killing more than 500 people and injuring over 1,000 others.
– Disney’s copyright protection on Steamboat Willie and the original Mickey Mouse expires as they enter the public domain.[118]
2025 – In New Orleans, Louisiana, 14 people are killed and 35 others injured during a vehicle-ramming and shooting attack by a moslem man inspired by the terrorist group ISIS, who was killed in a shoot-out with police.