What happened on 18 April?

13 events from the Ever-When timeline, ranked by how much they mattered.

1. 1506 St Peter's Basilica completed Vatican basilica designed by Bramante, Michelangelo, and Bernini; largest church in Christendom.
2. 1954 Nasser's rule of Egypt Pan-Arab nationalism at its height: the Suez nationalisation, the United Arab Republic, the Aswan Dam and defeat in 1967.
3. 1955 Bandung Conference 29 Asian and African states meet in Indonesia to promote decolonisation and cooperation; a precursor to the Non-Aligned Movement (founded 1961).
4. 1906 1906 San Francisco earthquake Devastating earthquake and fire.
5. 2008 Indian Premier League founded T20 cricket league transforms the global sport.
6. 1949 Ireland declares a republic The Republic of Ireland Act takes effect, formally leaving the Commonwealth.
7. 1951 Treaty of Paris establishes ECSC France, Germany, Italy and Benelux sign the European Coal and Steel Community treaty.
8. 1980 Zimbabwe independence Southern Rhodesia becomes the Republic of Zimbabwe under Robert Mugabe, ending white-minority rule after a long bush war.
9. 1942 Doolittle Raid American B-25s launched from a carrier bomb Tokyo and other cities; first US attack on the Japanese home islands.
10. 1835 Lord Melbourne's second premiership Melbourne tutors the young Queen Victoria in the business of monarchy while his majority drains away.
11. 1938 Superman debuts Action Comics #1 introduces Superman, creating the superhero genre that would dominate later popular culture.
12. 1864 The storming of Dybbøl Prussian infantry overrun Denmark's fortified line in four hours, deciding the war for Schleswig-Holstein — the first of Bismarck's three wars, and the testing ground for the breec
13. 1688 Germantown Quaker antislavery petition Four Pennsylvania Quakers write the first organised protest against African slavery in the colonies — 'those who steal or rob men, and those who buy or purchase them, are they not