Sir Martin Gilbert: Historian who became an authority on Churchill and on the Holocaust and served on Sir John Chilcot's Iraq Inquiry

Gilbert - historian and author of more than 80 books - became known for three main streams of work during his five-decade career

Gilbert in 2009 at the start of the Iraq Inquiry; he was, said Lord Chilcot, 'a kind and generous colleague' (PA)

It has been a week of two significant anniversaries. It is 50 years since Winston Churchill's funeral and 70 years since the liberation of Auschwitz. Sir Martin Gilbert, who has died aged 78 but lived to see both anniversaries, was a key figure in researching and documenting the people and events around both these landmarks of 20th century history.

Gilbert, historian and author of more than 80 books, became known for three main streams of work during his five-decade career. He was Churchill's official biographer, having taken over the task from the leader's son, Randolph; and as an historian of the Holocaust he wrote a number of highly regarded works on the subject. More recently, known for his meticulous research and attention to detail, he had been appointed as one of five panel members on the Iraq Inquiry led by Sir John Chilcot.

His motivating philosophy, he said, "has always been to write history from the human perspective, never to neglect the person known as 'the common man' – whether man or woman, or child". He would frequently cite Churchill's reply to the question of why the 20th century was known as the century of the common man: "It is called the century of the common man because in it the common man has suffered most."

Gilbert was born in London in 1936 to Peter and Miriam Gilbert. He was evacuated on the outbreak of war to Canada; on returning to Britain he continued his education at Highgate School and went up to Magdalene College, Oxford, where he read Modern History.

As a junior fellow at Merton College he had begun research on the life of Sir James Dunlop Smith, Private Secretary to Lord Minto, Viceroy of India during Edwardian British rule. But in 1962 his research was interrupted by an invitation from Randolph Churchill to become part of the team working on a biography of his father. Gilbert remembered him as a "hard taskmaster" who taught him "many aspects of the historian's craft".

He recalled: "For the next six years I would live at Oxford, and teach and write at Merton College, but be prepared to travel across country to work in the Churchill archive whenever Randolph summoned me." The first two volumes were published during 1966 and 1967.

Simultaneously, Gilbert was working alone on a single-volume biography of Churchill, which was published in 1966, encouraged and supported by the late leader's family. His postponed work on Smith finally appeared the same year. When Randolph Churchill died two years later, leaving the main project incomplete, Gilbert took over the role of official biographer. The biography and its companion volumes would occupy him for the next 20 years and remain the ultimate reference on Churchill's life and work.

The subject of the Holocaust had occupied Gilbert since his student days, when he had visited concentration camps in Poland. His The Holocaust: The Jewish Tragedy (1985) provides a masterful account of the Shoah, documenting its preparation and execution and the response by the Allies. The Holocaust survivor and historian Elie Wiesel read it on publication and declared that "this book must be read and reread". The two went on to collaborate on The Jews of Silence (2011), which tells the stories of Jews trapped behind the Iron Curtain.

In 1995 Gilbert retired as a Fellow of Merton College and was made an Honorary Fellow. He continued to write and lecture, also appearing frequently on radio and television. He accompanied prime ministers John Major and Gordon Brown on official visits to Israel in 1995 and 2008 and was knighted in 1995 for services to British history and international relations.

In documenting the Holocaust he took a particular interest in the lives of individuals, both Jews and non-Jews, whose stories might not otherwise come to public notice. Some of their accounts were published in his 2002 work The Righteous: The Unsung Heroes of the Holocaust. Asked in 2005 about Holocaust denial, he replied, "The number of deniers and the amount of denial literature is minuscule compared with the serious literature, not only the memoirs but the history books, the specialist books, and books which cater for every age group on the Holocaust... in that sense the Holocaust deniers have totally lost out."

Churchill and the Jews (2007) brought together the twin principal threads of his research career, examining the wartime leader's relationship with the Jews and with Zionism. He later commented: "From the first to the last day of the war, the fate of the Jews was something on which Churchill took immediate and positive action whenever he was asked to do so. In addition, in 1940 he refused to contemplate making peace with Hitler, and for the next four years used every fibre of his being to devise means of defeating Hitler."

When the Iraq War Inquiry, led by Sir John Chilcot, began its work in 2009, Gilbert was a logical choice for the panel with his combination of analytical skills and depth of historical knowledge. Chilcot described him as an "extraordinarily eminent historian" and a "kind and generous colleague". Karen Pollock, chief executive of the Holocaust Educational Trust, told The Independent: "Martin Gilbert was ... a close friend and supporter of the Holocaust Educational Trust... His great humility and the incredible warmth with which he engaged with Holocaust survivors truly set him apart."

Aside from his writing, Gilbert, who died following a long illness, was a keen cartographer, initially as a hobby and later professionally. His maps of wartime Europe have been published in his own atlases and in historical works by other authors. His most recent work in preparation is The Jews of Britain, due for publication in April next year.

MARCUS WILLIAMSON

Sir Martin Gilbert, historian and writer: born London 25 October 1936; FRSL 1977; CBE 1990; Kt 1995; married 1963 Helen Constance Robinson (marriage dissolved; one daughter), 1974 Susan Sacher (marriage dissolved; two sons), 2005 Esther Goldberg; died London 3 February 2015.