36 notable events from 1903.
- Karl Denke
Feb 21, 1903–Dec 20, 1924 · Germany
- Kishinev pogrom
Apr 6, 1903–Apr 9, 1903 · Moldova
- Iroquois Theatre fire
Dec 30, 1903 · United States
- Secession of Panama from Colombia
Nov 3, 1903 · Panama
- May Coup (Serbia)
May 28, 1903–May 29, 1903 · Serbia
- Ilinden–Preobrazhenie Uprising
Aug 2, 1903–Oct 1903 · North Macedonia
- Human Pavilion incident
1903 · —
- Brown Dog affair
Feb 1, 1903–Mar 1, 1910 · United Kingdom
- Winfield massacre
Aug 13, 1903 · United States
- Paris Metro train fire
Aug 10, 1903 · France
- Foundational crisis of mathematics
1903–1930 · —
- Fort Crampel Affair
Jul 14, 1903 · Central African Republic
- Yalu River concessions
May 1903 · North Korea
- Bombardment of Fort San Carlos
Jan 17, 1903 · Venezuela
- Heppner flood of 1903
Jun 14, 1903 · United States
- Shooting of the demonstration in Zlatoust (1903)
Mar 11, 1903–Mar 13, 1903 · Russian Federation
- Evansville race riot
Jul 1903 · United States
- Connellsville train wreck
Dec 23, 1903 · United States
- Robert Proctor (bibliographer)
Sep 5, 1903 · —
- North Inch disaster
Aug 1, 1903 · United Kingdom
- Lynching of David Wyatt
Jun 6, 1903 · United States
- Danville race riot
Jul 25, 1903 · —
- 1903 Manzikert earthquake
Apr 28, 1903 · Türkiye
- Glasgow St Enoch rail accident
Jul 27, 1903 · United Kingdom
- Silesia flood (1903)
Jul 17, 1903 · Poland
- 1903 Isfahan anti-Baháʼí riots
May 1, 1903 · Iran
- Water Riots
Mar 23, 1903 · Trinidad and Tobago
- Beano rail accident
Aug 27, 1903 · Italy
- United States Cartridge Company explosion
Jul 29, 1903 · United States
- Celebesstraat murder
Jul 25, 1903 · Netherlands
- 1903 Galicia flood
Jul 14, 1903 · Ukraine
- Rothenkirchen rail accident
Aug 17, 1903 · —
- 1903 Kuznetsk earthquake
Mar 12, 1903 · Russian Federation
- Herbolzheim rail accident
Dec 2, 1903 · Germany
- 1903 Mendoza earthquake
Aug 12, 1903 · Argentina
- Torremontalbo train collision
Jun 27, 1903 · Spain