King John of England affixed his seal to the Magna Carta at Runnymede, establishing for the first time that the king was subject to the rule of law. The document became the foundation of constitutional governance.

The Second Continental Congress unanimously appointed George Washington as Commander-in-Chief of the Continental Army, setting in motion the American Revolution's military campaign.

Charles Goodyear received a U.S. patent for vulcanisation, transforming natural rubber into a durable material that would become essential for tyres, industry, and everyday life worldwide.

Soviet cosmonaut Valentina Tereshkova launched aboard Vostok 6, becoming the first woman and first civilian to travel to space, completing 48 orbits of Earth over three days.

The Provisional IRA detonated a 1,500 kg truck bomb in Manchester's Arndale shopping district — the largest bomb detonated in Britain since WWII. Over 200 people were injured.