History

"Little Boy"(top)
"Fat Man"(bottom)

• During the end of World War II in 1945, the Allies of World War II successfully dropped two atomic bombs on the cities of Hiroshima and Nagasaki in Japan.  These were the only nuclear weapons used in war. 

• After firebombing campaign that destroyed many Japanese cities, the United States, the United Kingdom and the Republic of China demanded the surrender of Japan in the Potsdam Declaration on July 26, 1945 under the threat of "prompt and utter destruction".  

Tokyo before and after fire bombing

• Despite the destruction of some of its cities, Japan ignored the final warning of the Allies. Japan's decline of the Potsdam Declaration lead to the development of two nuclear weapons by the Manhattan Project. 



Hiroshima after bombing

• The Manhattan project was a former United States executive agency for the secret United States project set up in 1942 to develop atomic bombs for use in World War II.

• Hiroshima was a minor supply base for the Japanese military. The city was a communications center, a storage point, and an assembly area for troops. It was also one of several Japanese cities left purposely untouched by American bombing. On August 6, 1945, "Little Boy" was dropped on Hiroshima killing 90,000-166,000 people within the first two to four months of the bombing. 

Atomic bomb mushroom clouds over Nagasaki

• The city of Nagasaki had been one of the largest sea ports in southern Japan and was important to the war because of its wide-ranging industrial activity; including the production of ordnance, ships, military equipment, and other war materials. Nagasaki had never been subjected to large-scale bombing prior to the explosion of a nuclear weapon there. On August 1, 1945, however, a number of high-explosive bombs were dropped on the city. On August 9, 1945, "Fat Man" was dropped on Nagasaki killing 60,000-80,000 people within the first two to four months of the bombing.

   Japanese Foreign Minister Mamoru Shigemitsu signing the Instrument of Surrender on behalf of the Japanese Government, ending World War II.

• On August 15, 1945, Japan announced its surrender to the Allies, and signed the Instrument of Surrender on September 2, 1945, officially ending World War II.