Albert Einstein Einstein did not return to Germany. He settled in the United States and became an American citizen in 1940. On the eve of World War II, he endorsed a letter to President Franklin D. Roosevelt alerting him to the potential development of "extremely powerful bombs of a new type" and recommending that the US begin similar research. This eventually led to the Manhattan Project. Einstein supported the Allies, but he generally denounced the idea of using nuclear fission as a weapon. He signed the Russell–Einstein Manifesto with British philosopher Bertrand Russell, which highlighted the danger of nuclear weapons. He was
Albert Einstein in popular culture to be featured in the altered timeline in "Red Alert" and "" developing time travel technology for use by the Allies, and his fictional murder at the hands of the Soviets, also involving a time machine, is a central plot point of "". In "Mega Man", released in 1987, Dr. Wily's design is inspired by Albert Einstein, and was initially conceived to appear as a tall, thin scientist with a mustache, glasses, balding hair, and lab coat. In "Half-Life", one of the scientist models is based on Einstein's appearance. Albert Einstein in popular culture Albert Einstein has been the subject