What happened on 22 April?

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

1. 1509 Reign of Henry VIII Reign of Henry VIII (1509-1547) as King of England.
2. 1915 Second Battle of Ypres / first poison gas Germans use chlorine gas in mass attack — opens chemical warfare era.
3. 1175 BCE Penelope and the olive-tree bed Odyssey 23: she tests him one last time — move the bed. It cannot be moved: he built it round a living olive tree, and only they two know it.
4. 1519 Cortés lands at Veracruz Hernán Cortés disobeys Cuba governor's recall and lands ~600 men on the Mexican coast; scuttles his ships and marches inland.
5. 1904 Born: J. Robert Oppenheimer American physicist who led the Los Alamos lab building the atomic bomb.
6. 1978 One Love Peace Concert Amid near civil war between Jamaica's political gangs, Marley returns from exile to play in Kingston and draws rival leaders Michael Manley and Edward Seaga on stage to join hands
7. 1453 Mehmed hauls his fleet over the hills Blocked by the chain, Mehmed has seventy ships dragged overland on greased wooden rollers — over a 200-foot ridge, in a single night — into the Golden Horn behind the boom. The def
8. 1970 First Earth Day First Earth Day environmental teach-in across the US.
9. 1500 Cabral reaches Brazil Portuguese fleet under Pedro Álvares Cabral, bound for India, lands on the Brazilian coast; Portugal claims and colonises Brazil.
10. 1993 Mosaic makes the web visual Two programmers at an Illinois supercomputing centre release a free browser that puts images on the page next to the text and installs in minutes. Mosaic turns the web from a physi
11. 1529 Treaty of Saragossa Spain and Portugal partition the Pacific; complements Tordesillas; resolves dispute over the Moluccas.