Galtung experienced World War II in German-occupied Norway, and as a 12-year-old saw his father arrested by the Nazis. By 1951 he was already a committed peace mediator, and elected to do 18 months of social service in place of his obligatory military service. After 12 months, Galtung insisted that the remainder of his social service be spent in activities relevant to peace, to which the Norwegian authorities responded by sending him to prison, where he served six months.[9]