Short answers, pulled from the story.
The first Summer Olympic Games were held in Athens, Greece, from the 6th to the 15th of April 1896. The host city was chosen unanimously at a congress Pierre de Coubertin organised in Paris on the 23rd of June 1894.
Pierre de Coubertin, a French pedagogue and historian, founded the International Olympic Committee in 1894 with the goal of promoting international understanding through sporting competition. The IOC was established at the same Paris congress that selected Athens as the first host city.
The United States leads the all-time medal count for the Summer Olympics and has topped the medal table on 19 separate occasions. Only Great Britain has won at least one gold medal at every edition of the Summer Games.
A Palestinian group called Black September broke into the Israeli delegation's apartment in the Olympic village, killing two team members and taking nine others hostage. All nine hostages died in a firefight during a failed rescue attempt at the airport, bringing the total death toll to fifteen people including five of the attackers.
Cassius Clay, later known as Muhammad Ali, won the light-heavyweight boxing gold medal at the 1960 Rome Games. He later discarded that medal after being refused service at a whites-only restaurant in Louisville, Kentucky, and received a replacement medal at the 1996 Atlanta Olympics.
66 nations boycotted the 1980 Moscow Games following the Soviet Union's invasion of Afghanistan, including the United States, Canada, West Germany, and Japan. Only 80 nations competed, the smallest number since 1956.