The document summarizes key events surrounding the US bombing of Hiroshima and Nagasaki in August 1945 that ultimately led to Japan's surrender, ending World War II:
1) The US dropped an atomic bomb on Hiroshima on August 6th, destroying much of the city and killing around 80,000 people instantly. 2) Three days later on August 9th, a second atomic bomb was dropped on Nagasaki, killing tens of thousands. 3) In the aftermath of the bombings, Japan agreed to surrender on August 15th, bringing World War II to an end.