who was he?
He  was a United States Army Corps of Engineers officer.
Leslie Groves
 was a United States Army Corps of Engineers officer 
how did fighting between the united states and japan come to an end during world war 2 The surrender of Imperial Japan was announced by Japanese Emperor Hirohito on August 15 and formally signed on September 2, 1945, bringing the hostilities of World War II to a close. what was manhattan project? The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. who led this project? Major General Leslie Groves
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Leslie Groves [SEP] Introduction
Lieutenant General Leslie Richard Groves Jr. (17 August 1896 – 13 July 1970) was a United States Army Corps of Engineers officer who oversaw the construction of the Pentagon and directed the Manhattan Project, a top secret research project that developed the atomic bomb during World War II. The son of a U.S. Army chaplain, Groves lived at various Army posts during his childhood. In 1918, he graduated fourth in his class at the U.S. Military Academy at West Point and was commissioned into the U.S. Army Corps of Engineers. In 1929, he went to Nicaragua as part of an expedition to conduct a survey for the Inter-Oceanic Nicaragua Canal.