How World War II Ended

There are many factors that led to the end of world war II, however the factor relating to end of the US and Japanese war are detailed in this passage

Atomic Bombing of Hiroshima and Nagasaki

President Roosevelt died on April 12th 1945, suceeded by president Harry S. Truman. Truman wanted to end not only the war between America and Japan but the world war at large. He learned of the Manhattan project , a secret scientific effort to create an atomic bomb. After a successful testing of the weapon in Alamogordo, New Mexico. Truman issued a Potsdam declaration, demanding the surrender of Japanese government or consequences of unleashing destructive force on Japan.

When the Japanese government ignored the threat, American bomber dropped an atomic bomb on Hiroshima a manufacturing city of Japan, killing 80,000 people and tens of thousands more as a result of radiation exposure. When japan failed to surrender 3 days  after the bombing, a more deadly atomic bomb was released on Nagasaki, another city in Japan, killing 35,000 people and 50,000 more later on.

Shortly after the second bombing, the Japanese Emperor Hirohito, seeing that Soviet Union had declared war on Japan for occupying Manchuria in North Eastern China, decided that Japan must surrender. On August 15th, the emperor announced Japan's surrender in his first ever radio broadcast.

World war 2 ended officially on September 2nd 1945, when US General Douglas MacAuthor accepted Japan's formal surrender aboard the US battleship Missouri, anchored in Tokyo Bay. Followed by the global signing of agreements and treaties.