1901January 1901 January 1 The British colonies of New South Wales, Queensland, South Australia, Tasmania, Victoria and Western Australia federate as the Commonwealth of Australia; Edmund Barton becomes the first Prime Minister of Australia. Nigeria becomes a British protectorate. January 9 – Lord Kitchener reports that Christiaan de Wet has shot one of the "peace" envoys, and flogged two more, who had gone to his commando to ask the Burgher citizens of South Africa to halt fighting.
1904January 1904 January 7 – The distress signal CQD is established, only to be replaced 2 years later by SOS. January 8 – The Blackstone Library is dedicated, marking the beginning of the Chicago Public Library system. January 12 – The Herero Wars in German South West Africa begin. January 17 – Anton Chekhov's last play, The Cherry Orchard («Вишнëвый сад», Vishnevyi sad), opens at the Moscow Art Theatre directed by Constantin Stanislavski, 6 month's before the author's death.
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.
1902January 1902 January 1 The Nurses Registration Act 1901 comes into effect in New Zealand, making it the first country in the world to require state registration of nurses. On January 10, Ellen Dougherty becomes the world's first registered nurse. Nathan Stubblefield demonstrates his wireless telephone device in the U.S. state of Kentucky. January 8 – A train collision in the New York Central Railroad's Park Avenue Tunnel kills 17 people, injures 38, and leads to increased demand for electric trains and the banning of steam locomotives in New York City.
1920January 1920 January 1 Polish–Soviet War in 1920: The Russian Red Army increases its troops along the Polish border from 4 divisions to 20. Kauniainen, completely surrounded by the city of Espoo, secedes from Espoo as its own market town. January 3 – The 1920 Xalapa earthquake in Mexico kills over 600 people, making it the second deadliest in the country. January 7 – Russian Civil War: The forces of Russian White Admiral Alexander Kolchak surrender in Krasnoyarsk; the Great Siberian Ice March ensues.
1894January 4 – A military alliance is established between the French Third Republic and the Russian Empire. January 7 – William Kennedy Dickson receives a patent for motion picture film in the United States. January 9 – New England Telephone and Telegraph installs the first battery-operated telephone switchboard, in Lexington, Massachusetts. February 12 French anarchist Émile Henry sets off a bomb in a Paris café, killing one person and wounding twenty.