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On April 30, 1945, with Soviet troops fighting just a few blocks from his bunker in Berlin, Adolf Hitler committed suicide alongside his wife Eva Braun, whom he had married the day before. Their bodies were burned in the Chancellery garden according to his instructions. Hitler's death marked the end of the Third Reich; Germany surrendered eight days later, on May 8, 1945.

On April 30, 1975, tanks of the North Vietnamese Army broke down the gates of the Independence Palace in Saigon, ending the Vietnam War with Communist victory. The image of helicopters evacuating the last Americans from the roof of the US Embassy is one of the most powerful icons in Cold War history. Saigon was renamed Ho Chi Minh City.

On April 30, 1993, CERN in Geneva published a document placing World Wide Web technology in the public domain entirely free of charge, waiving any patent or intellectual property rights. Tim Berners-Lee's and CERN's decision not to charge for the WWW was fundamental in allowing the internet to become an open global network rather than a private technological monopoly.