On this day in 1904, the summer Olympics kicked off in Saint Louis, Missouri! It was the 3rd Olympiad in the modern era and the first Olympic Games held in the United States. Because of tensions caused by the Russo-Japanese War and difficulties traveling to St. Louis in 1904, there were very few athletes from outside the U.S. and Canada. Boxing, dumbbells, freestyle wrestling, and the decathlon all made their debut. And the current 3 medal format of gold, silver, and bronze was introduced at the 1904 Olympics. Not surprisingly, the U.S. did very well, winning 231 of the 280 total medals awarded that year! Learn more here.