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On June 23, 2016, citizens of the United Kingdom voted in a referendum to leave the European Union — Brexit — with 51.9% of the vote, in the most unexpected political result in twenty-first-century Europe. The decision triggered years of political turbulence, the resignation of several prime ministers and the UK's effective departure from the EU on January 31, 2020.

On June 23, 1868, American inventor Christopher Latham Sholes obtained the patent for the first practical typewriter in history, which introduced the famous QWERTY keyboard, designed to prevent keys from jamming. The patent was sold to the company E. Remington & Sons in 1873. The QWERTY keyboard became the global standard and remains the world's most widely used today.

On June 23, 1993, Denmark's national team won the European Championship against defending champions Germany 2-0 in Gothenburg — the greatest unlikely triumph in football history. The Danes had been excluded from the tournament and were only readmitted 11 days before the start when Yugoslavia was disqualified due to the war. With barely any preparation, Denmark eliminated France, Netherlands and Germany.