1899January 1 Spanish rule ends in Cuba, concluding 400 years of the Spanish Empire in the Americas. Queens and Staten Island become administratively part of New York City. January 2 Bolivia sets up a customs office in Puerto Alonso, leading to the Brazilian settlers there to declare the Republic of Acre in a revolt against Bolivian authorities. The first part of the Jakarta Kota–Anyer Kidul railway on the island of Java is opened between Batavia Zuid (Jakarta Kota) and Tangerang.
1903January 1903 January 1 – Edward VII is proclaimed Emperor of India. January 4 – Topsy, a female Asian circus elephant, is killed by electrocution at Luna Park, Coney Island, New York City. January 19 – The first west–east transatlantic radio broadcast is made from the United States to England (the first east–west broadcast having been made in 1901). January 17 – 13 days after Topsy's death, the Edison Manufacturing Company released the short, black-and-white, silent documentary film Electrocuting an Elephant, showing the footage of Topsy's electrocution.
1874January 1 – New York City annexes The Bronx. January 2 – Ignacio María González becomes head of state of the Dominican Republic for the first time. January 3 – Third Carlist War: Battle of Caspe – Campaigning on the Ebro in Aragon for the Spanish Republican Government, Colonel Eulogio Despujol surprises a Carlist force under Manuel Marco de Bello at Caspe, northeast of Alcañiz. In a brilliant action the Carlists are routed, losing 200 prisoners and 80 horses, while Despujol is promoted to Brigadier and becomes Conde de Caspe.
1973January 1973 January 1 – The United Kingdom, the Republic of Ireland and Denmark enter the European Economic Community, which later becomes the European Union. January 15 – Vietnam War: Citing progress in peace negotiations, U.S. President Richard Nixon announces the suspension of offensive action in North Vietnam. January 17 – Ferdinand Marcos becomes President for Life of the Philippines. January 20 – Richard Nixon is sworn in for a second term as President of the United States.
1913January 1913 January 3 – First Balkan War: Greece completes its capture of the eastern Aegean island of Chios, as the last Ottoman forces on the island surrender. January 13 – Edward Carson founds the (first) Ulster Volunteer Force, by unifying several existing loyalist militias to resist home rule for Ireland. January 18 – First Balkan War: Battle of Lemnos – Greek admiral Pavlos Kountouriotis forces the Turkish fleet to retreat to its base within the Dardanelles, from which it will not venture for the rest of the war.
1972Within the context of Coordinated Universal Time (UTC) it was the longest year ever, as two leap seconds were added during this 366-day year, an event which has not since been repeated. (If its start and end are defined using mean solar time [the legal time scale], its duration was 31622401.141 seconds of Terrestrial Time (or Ephemeris Time), which is slightly shorter than 1908). January 1972 January 1 – Kurt Waldheim becomes Secretary-General of the United Nations.