Unlike most counties who celebrate the day on August 14th, the United States celebrate Victory over Japan Day (V-J Day) in September 2.
On this day in 1945, the Japanese Instrument of Surrender was formally signed on board USS Missouri. By the end of July 1945, the imminent defeat of Japan in the Second World War became obvious. Atomic bombings of the cities of Hiroshima and Nagasaki and a failed military coup became the last straw that made Emperor Hirohito announce the surrender of Japan to the Allies.
Japan surrendered on August 14/15 (depending on the time zone), 1945, and in many countries this date is observed as Victory over Japan Day.The formal signing of the Japanese Instrument of Surrender took place aboard USS Missouri in Tokyo Bay on September 2, 1945. President Harry S. Truman designated September 2 as Victory over Japan Day.
The name V-J Day was selected to remind of V-E Day (Victory in Europe Day) celebrated on May 8. V-J Day is also sometimes referred to as Victory in the Pacific Day (V-P Day). Although V-J Day is celebrated throughout the United States, it is recognized as an official holiday only in Rhode Island, where it is called Victory Day.
Instead of September 2, Victory Day is celebrated on the second Monday in August.