Since 1945 a total of nine persons and organizations have been awarded the Nobel Peace Prize partly or wholly in recognition of their work against nuclear weapons. This article explains how these awards came about. The Norwegian Nobel Committee’s view on nuclear weapons evolved from a state of indifference—if not outright approval—in the first decade after the Second World War, through a period of growing concerns in the 1950s, sixties and seventies, to an increasingly clear stand in favor of nuclear disarmament in the 1980s and nineties, a process, it is argued, that was driven by both domestic political factors and international developments.