In the final years of his life, Ernest Hemingway tried to convince friends and family that the FBI was following him, but they just told him he was paranoid.
In late 1960, he was admitted to the Mayo Clinic in Minnesota, where he received electroshock therapy. Even there, he refused to speak freely, convinced someone was listening.
In July 1961, Hemingway died by suicide at his home in Idaho.
Years after he died, the FBI released files showing that they had been monitoring him for the last 20 years of his life.