The hunt for Machiu Picchu
- Agustín Lizárraga discovers Machu Picchu on July 14, 1902.
- The Tour de France starts for the first time in 1903.
Food
- U.S. New Haven, Connecticut Louis Lassen of Louis’ Lunch makes the first modern-day hamburger sandwich. According to family legend, one day in 1900 a local businessman dashed into the small New Haven lunch wagon and pleaded for a lunch to go. According to the Lassen family, the customer, Gary Widmore, exclaimed “Louie! I’m in a rush, slap a meatpuck between two planks and step on it!”. Louis Lassen, the establishment’s owner, placed his own blend of ground steak trimmings between two slices of toast and sent the gentleman on his way, so the story goes, with America’s alleged first hamburger being served.
Wars
- Second Boer War ends.
- Philippine–American War takes place (1899–1902).
- The Kuwaiti–Rashidi war takes place (1900–1901).
- Russo-Japanese War establishes the Empire of Japan as a world power.
- Battle of Riyadh was a minor battle of the Unification of Saudi Arabia.
- Battle of Dilam was a major battle of the Unification War between Rashidi and Saudi rebels.
- First Saudi–Rashidi War was engaged between the Saudi loyal forces of the newborn Emirate of Riyadh versus the Emirate of Ha’il.
- The Ottomans invade Persia and capture a strip of territory (1906).
Internal conflicts
- The Boxer Rebellion ends.
- The Russian Revolution of 1905.
- The Mesopotamia uprising of 1906.
- Demand for Home Rule for Ireland.
- Herero and Namaqua Genocide in German South-West Africa (modern Namibia).
- Kurdish uprising in Bitlis against the Ottoman Empire in 1907.
- January 1, 1901, British colonies in Australia federate, forming the Commonwealth of Australia.
Decolonization
- May 20, 1902 – Cuba gains independence from the United States
- June 7, 1905 – The Norwegian Parliament declares the union with Sweden dissolved, and Norway achieves full independence.
- October 5, 1908 – Bulgaria declares its independence from the Ottoman Empire.
Natural disasters
- August 7, 1900 – A 40-foot-tall tornado struck New Rochelle, New York, US, killing an unknown amount of people.
- September 8, 1900 – A powerful hurricane hits Galveston, Texas, US, killing about 8,000.
- April 19, 1902 – A magnitude 7.5 earthquake rocks Guatemala, killing 2,000.
- May 8, 1902 – In Martinique, Mount Pelée erupts, destroying the town of Saint-Pierre and killing over 30,000.
- December 25, 1902 – A large hurricane struck the countries of Sweden and Denmark, leading to the deaths of 50 people.
- February 26-27, 1903 – A large extratropical cyclone known as Storm Ulysses swept through the British Isles and led to the deaths of 30 people.
- April 7, 1906 – Mount Vesuvius erupts and devastates Naples.
- April 18, 1906 – The 1906 San Francisco earthquake (estimated magnitude 7.8) on the San Andreas Fault destroys much of San Francisco, US, killing at least 3,000, with 225,000–300,000 left homeless, and $350 million in damages.
- September 18, 1906 – A typhoon and tsunami kill an estimated 10,000 in Hong Kong.
- January 14, 1907 – An earthquake in Kingston, Jamaica kills more than 1,000.
- June 30, 1908 – The Tunguska event or “Russian explosion” near the Podkamennaya Tunguska River in Krasnoyarsk Krai, Siberia, Russian Empire occurs resulting in the flattening 2,000 km2 (770 sq mi) of forest. It is believed to have been caused by the air burst of a large meteoroid or comet fragment, at an altitude of 5–10 kilometres (3–6 mi) above the Earth‘s surface.[15][16][17]
- December 28, 1908 – An earthquake and tsunami destroys Messina, Sicily and Calabria, killing over 80,000 people.

Science
- 1900 – Planck’s law of black-body radiation
- 1900 – Quantum Hypothesis by Max Planck[22][23][24][25][26]
- 1900 – Seismographs built in the University of California, Berkeley
- 1902 – Practical air conditioner designed by Willis Carrier
- March 17, 1905 – Annus Mirabilis papers – Albert Einstein publishes his paper “On a heuristic viewpoint concerning the production and transformation of light”, in which he explains the photoelectric effect, using the notion of light quanta. For this paper Einstein received the Nobel Prize for Physics in 1921.
- May 11, 1905 – Annus Mirabilis papers – Albert Einstein submits his doctoral dissertation “On the Motion of Small Particles…”, in which he explains Brownian motion.
- June 30, 1905 – Annus Mirabilis papers – Albert Einstein publishes the article “On the Electrodynamics of Moving Bodies”, where he reveals his theory of special relativity.
- September 27, 1905 – Annus Mirabilis papers – Albert Einstein submits his paper “Does the Inertia of a Body Depend Upon Its Energy Content?”, in which he develops an argument for the equation E = mc2.
- 1908 – the Geiger counter (measures radioactivity) is invented by Hans Geiger
- Pierre and Marie Curie discover the elements radium and polonium, they coin the term radioactivity. In 1901, Harriet Brooks and Ernest Rutherford build on their work and contribute to the discovery of the element radon.
- The Bacillus Calmette-Guérin (BCG) immunization for tuberculosis is first developed.
Music
- Giacomo Puccini‘s opera Tosca (poster pictured), based on the play La Tosca by French dramatist Victorien Sardou, premiered at the Teatro Costanzi in Rome.
Film
- 1900 Release of the first film version of Hamlet, an adaptation of the duel scene, with French actress Sarah Bernhardt playing the title role and accompanying recorded sound.
- 1900 Making of the first film to feature the detective character Sherlock Holmes, Sherlock Holmes Baffled, by the American Mutoscope and Biograph Company.
- Jeanne d’Arc becomes the first film of considerable length (10 minutes) to be shown entirely in colour 1900
- 1901 Georges Méliès‘ film The Coronation of Edward VII (a staged simulation with inserted actuality footage) is first shown in London on the evening of the Coronation itself.
- 1901 actor/producer Méliès premières the first science fiction film, the silent A Trip to the Moon (Le Voyage dans La Lune), at the Théâtre Robert-Houdin in Paris, France; it proves an immediate success. One scene features the animated human face of the Moon being struck in the eye by a rocket.
- 1905 Aleksandr Khanzhonkov begins filming his first documentaries.
- The Misadventure of a French Gentleman Without Pants at the Zandvoort Beach, the oldest surviving Dutch fictional film is released by Alberts Frères. Later to be included in the canon of Dutch cinema as released by the Netherlands Film Festival.
- 1906 The world’s first feature film, The Story of the Kelly Gang, is released.
- 1908 Pathé invents the newsreel that was shown in cinemas prior to a feature film
- 1909 Mr. Flip is released, the first film to feature someone being hit in the face with a pie.