The 20th century
13,455 sourced entries across 100 documented years, grouped into 10 decades. A century here runs 1900–1999 rather than 1901–2000, so its decades sit inside it exactly.
Decades
- The 1900s — 10 years, 964 entries
- The 1910s — 10 years, 1,149 entries
- The 1920s — 10 years, 1,156 entries
- The 1930s — 10 years, 1,139 entries
- The 1940s — 10 years, 1,625 entries
- The 1950s — 10 years, 1,386 entries
- The 1960s — 10 years, 1,700 entries
- The 1970s — 10 years, 1,628 entries
- The 1980s — 10 years, 1,369 entries
- The 1990s — 10 years, 1,339 entries
By subject
- Geopolitics & Diplomacy in the 20th century — 2,030 entries
- Conflict & Security in the 20th century — 1,978 entries
- Culture & Society in the 20th century — 1,318 entries
- Technology & Infrastructure in the 20th century — 1,117 entries
- Disasters & Accidents in the 20th century — 1,068 entries
- Science & Discovery in the 20th century — 841 entries
- Crime & Justice in the 20th century — 791 entries
- Climate & Environment in the 20th century — 549 entries
- Health & Medicine in the 20th century — 380 entries
- Economy & Finance in the 20th century — 369 entries
- Exploration & Expansion in the 20th century — 351 entries
- Religion & Belief in the 20th century — 309 entries
A few of the years
- 1956April 19 – British diver Lionel (Buster) Crabb (working for MI6) dives into Portsmouth Harbour, to investigate a visiting Soviet cruiser, and vanishes.
- 1996July 5 – Dolly the sheep, the first mammal to be successfully cloned from an adult cell, is born at the Roslin Institute in Midlothian, Scotland, UK.
- 1997January 11 – Turkey threatens Cyprus on account of a deal to buy Russian S-300 missiles, prompting the Cypriot Missile Crisis.