JOHN KEEGAN:SIR JOHN Keegan, who has died aged 78, possessed a rare ability to describe warfare from the standpoint of the frontline soldier. For this he depended in great part on imagination, since poor health prevented him from wearing a uniform.
It was only in 1984 that he acquired a close-up view of battle (in the Lebanese civil war), which he described as physically disgusting and very frightening.
His third book, The Face of Battle (1976), made his name as a fine writer and is still widely regarded as his best despite more than 20 other works.
Keegan was five when the second World War broke out. His father came from an Irish Catholic family and had served in the first World War, but when the second came, he was a schools inspector, taking responsibility for the welfare of hundreds of evacuees. So, in 1939, the family left Clapham, in London, where Keegan was born, for Somerset, southwest England.
At 13, after he returned to London, Keegan's education at the Jesuit Wimbledon College in southwest London was interrupted when he was hospitalised for eight months for a tubercular hip. The condition left him with a hip "frozen" by a bone operation and a permanent limp. He won a scholarship to study history at Balliol College, Oxford, but another year-long bout of TB delayed his start.
In 1957 he graduated. Following two years of writing political analyses at the US embassy in London, in 1960 Keegan was appointed a lecturer in military history at the Royal Military Academy, Sandhurst, in southeast England, where he worked for 26 years. He wrote potted military histories before starting The Face of Battle, published when he was 42. He was moved to write it by the realisation that neither he nor his cadet students had experienced the warfare they were studying. It has remained in print ever since.
But works such as The Mask of Command (1987) showed that he understood generalship as well as life in the trenches. He made a point of visiting the sites of the battles he described.
In 1986 Keegan joined the London-based Daily Telegraph as defence correspondent, later defence editor until his death. The books continued to appear in a steady, prize-winning stream. But his journalistic output was very influential. Highly conservative, at least in the non-political sense, he overcame initial doubts to become a supporter of the Falklands war in 1982 under the nom de plume of Patrick Desmond in the London-based Spectator magazine, and of the first Iraq war eight years later under his real name. He was appointed Officer of the Order of the British Empire (OBE) in 1991.
Keegan was knighted in 2000 and further honoured with membership of the Commonwealth War Graves Commission. More ill-health dogged his later years when he was struck by spinal problems, then had a leg amputated. In April 2009 he had a stroke, but made a remarkable partial recovery.
He is survived by his wife of more than 50 years, the biographer Susanne Everett, two daughters and two sons.
John Desmond Patrick Keegan, born May 15th, 1934; died August 2nd, 2012