A Roman Catholic sociology professor, writer and peace activist Gordon Zahn co-founded the US branch of the international Catholic peace organisation Pax Christi. One of his enduring legacies was to have publicised the story of Franz Jaegerstatter, an Austrian peasant executed in 1943 for refusing to fight for Hitler.

Initially, Zahn's account of Jaegerstatter's resistance sparked outcry in 1960's America and a German Cardinal tried to suppress its publication arguing it would merely serve “the enemies of the Church.” Eventually it led to Jaegerstatter being beatified, or placed on the path to sainthood by the Vatican last October.

A father of three, Franz Jaegerstatter had been advised by his local bishop in Linz that family obligations made it excusable for him to join the Nazis. Saying “I cannot serve both Hitler and Jesus” Jagerstatter refused to do so, encouraged by a dream he had had in 1938 in which he saw large crowds rushing to board a beautiful train and heard a voice saying “this train is going to hell”. A vision of suffering followed. Later, Jaegerstatter wrote that the dream was an allegory for the Nazi's exaltation of patriotism and war.

“His was, at least to me, the real story,” explained Zahn. “A priest - given his calling, his education, his training - might be expected to take such a stand; but the witness of a simple peasant.. deserved more intensive study. The crucial lesson to be learned,” Zahn wrote “is that, however hopeless the situation… the Christian need not despair. Instead he can and should be prepared to accept and assert moral responsibility for his actions.”

Zahn's account of Jaegerstatter's life entitled In Solitary Witness played a crucial role during Vatican II, in shaping Catholic doctrine on pacifism. Jaegerstatter was cited by the British Jesuit, Archbishop Thomas Roberts as a model for all Christians, and later Zahn was invited to give a talk on pacifism and Christianity to the English and Welsh bishops finding them more receptive to the concept than their counterparts in the United States, some of whom such as Cardinal Spellman, the Archbishop of New York, were openly pro-military. Vatican II's Pastoral Constitution on the Church in the Modern World recognised for the first time, the right to be a conscientious objector.

But Zahn considered it an even greater triumph when, following decades of resistance, the US Catholic hierarchy acknowledged the right of Catholics to be pacifists as well as their right to fight in a Just War. This breakthrough occurred in the bishops' 1983 pastoral letter: War and Peace: the Challenge of God's Promise and Our Response. While drafting it, the Catholic hierarchy had interviewed Caspar Weinberger, then US Defense Secretary as well as generals and pacifists. Zahn was a primary consultant on the document, ghost-writing a section, at the request of his local bishop.

Gordon Zahn was born out of wedlock in 1918, the son of a man named Roach but later adopted the surname of his stepfather. By adulthood he was a convinced pacifist, and spent most of the war doing civilian public service, working with the mentally ill in a Baltimore hospital. His report on the neglect and mistreatment of patients there was published in The Baltimore Sun and provided the basis for long-term reforms to the treatment in the US of the mentally ill.

Openly declaring he was a conscientious objector on his college application forms, Zahn ran into trouble after his first year at St John's, a Benedictine College in Minnesota. He had been given a tuition grant and access to a job to fund his living expenses, but many on the staff were ex-war chaplains who objected to a grant being given to a pacifist. The college prior wrote to Zahn suggesting he drop out for a year or so “until tempers had cooled”. Zahn offered to pay his own tuition fees and, evicted from college residence, spent a night or so sleeping in his car while the Sociology faculty debated his future. Eventually he graduated from St Thomas' College, Minnesota and in 1953 obtained his PHD from the Catholic University of America in Washington. Later he taught Sociology at Loyola University, Chicago, a Jesuit institution. Attempts to publish his book German's Catholics and Hitler's War: a Study in Social Control at Loyola failed and it was eventually published by a branch of the British Catholic publishing firm Sheed&Ward, but some Catholics decried the book as being “intentionally defamatory” asking why Zahn was permitted to continue teaching at a Catholic university. In 1968, he transferred to the University of Massachussetts-Boston. Four years later Zahn and Eileen Egan founded Pax Christi USA, the American branch of an organisation originally established in postwar Europe to help reconcile French and German Catholics. From 1982 - 90 Zahn was director of the Pax Christi centre on Peace and Conscience in Washington. A dapper man, he inspired unusual reverence in his fellow Americans (they were said to bow in his presence).

Gordon Zahn was born on August 7, 1918. He died of Alzheimer's Disease on December 9, 2007 aged 89