Sir Joseph Rotblat

Nobel Peace Prize laureate and anti-nuclear campaigner

Born: 4 November, 1908, in Warsaw, Poland.

Died: 31 August, 2005, in London, aged 96.

JOSEPH Rotblat spent the early part of his career researching the nuclear bomb and joined the Manhattan Project during the war working on the atomic bomb. By late 1944, Rotblat was convinced the Germans did not have the scientific knowledge to manufacture a bomb so he, through conscience, returned to Britain where he campaigned with other academics for a test-ban treaty. His fearless association with the Campaign for Nuclear Disarmament resulted in Rotblat being one of the original members of the Pugwash Conference that brought together leading scientists. As their influence grew (for many years Pugwash was the only scientific contact between the East and the West) they became involved in advising on the Test Ban Treaty and biological weapons.

Joseph Rotblat got a masters degree in physics at Warsaw University and in 1939 was invited by James Chadwick to join his research team at Liverpool University. Their work was acknowledged worldwide as one of the most innovative in nuclear physics: they were among the first to show that an atomic bomb was possible. So Chadwick's entire team went, in 1944, to Los Alamos in New Mexico to work on the Manhattan Project.

Within months, the United States intelligence service had determined that the Germans could not develop an atomic bomb- despite all the talk from Hitler of a "secret weapon" - and Rotblat resigned. He foresaw that the nuclear bomb would be used as a bargaining tool between the two super powers in the post-war years. His decision caused an instant security worry - he had refused to take out British nationality - and Rotblat left under a severe cloud. The American authorities were convinced he would go to Poland and divulge the atomic secrets to the Russians. Rotblat, a man of high moral calibre, had worked on the bomb to prevent German superiority. He was horrified when they were used in Japan and was horrified at their destructive quality.

Rotblat had married in Poland before the war and despite his best endeavours was unable to spirit his wife out before the Nazis arrived in Warsaw. She was to die in a concentration camp. He returned from Los Alamos to lecture at Liverpool and was also director of research into nuclear physics. In 1950, he accepted the chair of professor of physics at St Bartholomew's Hospital where he remained until he retired in 1976. In that year he was visiting professor of international relations at Edinburgh University.

In 1955, Rotblat joined Albert Einstein and Bertrand Russell in publishing a manifesto drawing attention "to the impending destruction of the human race". Poignantly, they concluded their argument: "Which is it to be, then?" The three eminent scientists called for a conference to discuss disarmament and the abolition of war.

This was realised in 1957 by a Canadian industrialist who funded a meeting in Pugwash, Nova Scotia. It was an era of high tension with the Cold War at its height. Sympathy for the attitudes of Pugwash was not widespread. But it brought together high-ranking scientists from both sides of the Iron Curtain and political discussion was open and free. A degree of trust evolved between both sides and Pugwash has convened every year since.

Rotblat was always keen that Pugwash maintained a low profile but its influence at the highest levels was undoubted. It advised on the 1963 Partial Test Ban Treaty, the 1972 Biological Weapons Convention and, in the same year, the Anti-Ballistic Missile Treaty. Pugwash also played a significant, but little known, part bringing about the Henry Kissinger talks in 1967 between the US and Vietnam.

As Pugwash's first secretary-general (and president from 1988), Rotblat was instrumental in launching and advancing many of these initiatives. His calm and diplomatic manner combined with a supreme patience and willingness to listen and consult proved invaluable.

In the calmer days of the post-Cold War years, Rotblat turned his attention to raising concerns about the use of a pre-emptive nuclear strike against a non-nuclear nation. A year ago, his energy undimmed, Rotblat and Mikhael Gorbachev launched a conference in London to raise awareness of the increasing dangers of the proliferation of nuclear arms.

Rotblat remained devoted to his work and was seldom interviewed. He wrote prolifically in learned magazines (often upsetting conventional thought) and published over 30 books. He campaigned tirelessly for better treatment of the victims of nuclear fallout illness. All this activity left little time for hobbies and a personal life: he never remarried and his house in north London was a mass of books, papers and notes. He preferred this anonymous persona so it was only fitting that in 1995 not only did Rotblat and the Pugwash group receive the Nobel Prize for Peace but also he was made a Fellow of the Royal Society. Both honours, many colleagues considered, were long overdue. In 1992, he had been awarded the Albert Einstein Peace Prize and he was knighted in 1998.