On this day in history - June 15

What Happened On This Day – June 15

• 1991 Mount Pinatubo explodes

  The stratovolcano's eruption was one of the most violent of the 20th century. About 800 people died, but the event had also global consequences. For example, it caused a global temperature drop of 0.5 °C (0.9 °F).

• 1977 Spain holds the first free elections since 1936

  The transition to democracy followed nearly four decades of right-wing dictatorship under Francisco Franco. Adolfo Suárez became Spain's first democratically elected Prime Minister.

• 1954 The Union of European Football Associations is founded

  The UEFA is the umbrella organization for association football in Europe. It comprises 54 member countries in Europe and Asia.

• 1844 Charles Goodyear patents vulcanization

  The American inventor is credited with developing the basic concept of strengthening rubber by adding sulfur or similar materials. Vulcanized rubber is today used for a wide array of products, such as tires and shoe soles.

• 1667 The first human blood transfusion is administered

  Jean-Baptiste Denys, physician to King Louis XIV of France, transfused sheep blood into a 15-year-old boy. He survived, most likely due to the relatively small amount of blood used.