Who was vice president during the Manhattan Project?

During the Manhattan Project, which took place during World War II, the Vice President of the United States was Harry S. Truman. He assumed office in 1945, after serving as Vice President under Franklin D. Roosevelt. While Truman was not directly involved in the project, he became aware of it shortly before Roosevelt's death in April 1945, and he would later make the decision to use the atomic bombs developed through the project.