1900


As of March 1, when the Julian calendar acknowledged a leap day and the Gregorian calendar did not, the Julian calendar fell one day farther behind, bringing the difference to 13 days until February 28, 2100.

Summary

Political and military

The year 1900 was the end of the 19th century and the beginning of the 20th century. Two days into the new year, the U.S. Secretary of State John Hay announced the Open Door Policy regarding China, advocating for equal access for all nations to the Chinese market. The Galveston hurricane would become the deadliest natural disaster in United States history, killing between 6,000 and 12,000 people, mostly in and near Galveston, Texas, as well as leaving 10,000 people homeless, destroying 7,000 buildings of all kinds in Galveston. As of 2025, it remains the fourth deadliest Atlantic hurricane on record.
An ongoing Boxer Rebellion in China escalates with multiple attacks by the Boxers on Chinese and European civilians, killing hundreds; the rebellion would progress with the Russian Empire's invasion of Manchuria and the Battle of Peking. During the Scramble for Africa, the Battle of Kousséri would see French forces secure their domination of Chad, which would become a French colony. Britain would annex the South African Republic and the Orange Free State in Southern Africa, becoming the Orange River Colony until 1910.
For Britain, developments such as the Battle of Platrand, Battle of Spion Kop and the Battle of Paardeberg in the Second Boer War highlighted the harsh nature of Boer guerrilla tactics. The British Labour Party was founded in 1900, emerging out of the Labour movement and socialist parties of the 19th century; it would go on to become a major political force in Britain after the First World War. The Federation of Australia is enacted, marking the unification of its colonies into a single country.

Science

Four main scientific discoveries were achieved in the year 1900:
  1. Max Planck formulates Planck's law of black-body radiation, marking the birth of modern quantum mechanics, which would revolutionize humanity's understanding of the universe, leading to groundbreaking discoveries in technology, energy, and the fabric of reality itself.
  2. Botanist Hugo de Vries would rediscover Mendel's laws of heredity, laying the foundation for the field of genetics.
  3. The ABO blood group system, which becomes fundamental in transfusion medicine is discovered by Karl Landsteiner, saving countless numbers of lives across the globe.
  4. Gamma Rays are discovered by French physicist Paul Villard, while studying uranium decay, unveiling the mystery of the universe's most powerful phenomena and marking an important advancement in nuclear physics.

    Cultural and artistic

's opera Tosca premiers, one of the most frequently performed operas worldwide, a melodramatic piece set in Rome in June 1800, with the Kingdom of Naples's control of Rome threatened by Napoleon's invasion of Italy. It contains depictions of torture, murder, and suicide, as well as some of Puccini's best-known lyrical arias.
L. Frank Baum, an American author, publishes The Wonderful Wizard of Oz, a cornerstone of American children's literature, marking the first book of the Oz series.

Miscellaneous

The U.S. Senate accepts the British-German Treaty of 1899 on January 14. This formally ended U.S. claims to the Samoan Islands. The U.S.-UK Treaty for a Central American Canal would be signed on February 5. While the initial plan for a Nicaraguan canal did not materialize, this treaty laid the groundwork for the construction of the Panama Canal, a project of immense geopolitical and economic importance.
The year 1900 also marked the Year of the Rat on the Chinese calendar.

Events

January

  • c. January – The first Michelin Guide is published for French motorists.
  • January 2 – U.S. Secretary of State John Hay announces the Open Door Policy to promote American trade with China.
  • January 6 – Second Boer War: Boers attempt to end the Siege of Ladysmith, which leads to the Battle of Platrand.
  • January 14
  • * Puccini's opera Tosca premieres in Rome.
  • * The U.S. Senate accepts the British-German Treaty of 1899, in which the United Kingdom renounces its claims to the American Samoa portion of the Samoan Islands.
File:Boers at Spion Kop, 1900 - Project Gutenberg eText 16462.jpg|thumb|Second Boer War: Boers at Spion Kop