A former editor of one of the world’s oldest and most respected medical journals, who was among the first group of medics to enter and liberate the notorious Bergen-Belsen concentration camp during the Second World War, has died aged 101.

Dr Ian Douglas-Wilson, who was born in 1912 and died at Magnolia Court Care Home, in Granville Road, Childs Hill, on October 15, was editor of The Lancet for 12 years and gained a strong reputation as a radical and fearless leader of the journal.

Raised in Harrogate, Yorkshire, by his doctor father and mother, he began an extraordinary and varied career in medicine after graduating from Edinburgh University.

A short period working in Dublin helping to deliver newborns was followed by a stint as a GP in Pembrokeshire, but his career took a life-changing shift after he enlisted in the Royal Army Medical Corps following the outbreak of the Second World War.

His work treating servicemen who suffered from the effects of what is now termed post-traumatic stress disorder (PTSD) saw him become one of the first to publish a paper on the impact of war and conflict on mental health.

In April 1945 he became one of the first medics to enter the notorious Bergen-Belsen concentration camp in Germany when it was liberated by British troops.

Upon entering he and fellow soldiers discovered 53,000 prisoners inside, most of them half-starved and seriously ill, and some 13,000 unburied corpses.

His son, David Wilson, says the ordeal stayed with him his whole life. “He used to talk about it at great length to us,” he said.

A universal social consciousness saw Dr Douglas-Wilson house German prisoners of war on his return at Christmas and also open his home to Hungarian refugees fleeing Soviet oppression during the 1950s.

His principled approach to life extended throughout his 30-year career and in his work for The Lancet.

After rising up the ranks he followed a long tradition of editors who never shied from challenging the norm. Despite retiring early and moving to Cricklewood to take care of his poorly wife, his legacy at the journal remains.

Staff and readers remember his editorship for its strong support for osteopathy, for his unflinching support of universal care and the NHS and for his ground-breaking criticism of the “corrupt and biased” peer-review system.

“He was one of the great editors of The Lancet,” said current editor Dr Richard Horton. “He believed in the power of science to change not only lives, but also whole societies, and he saw medicine as a political endeavour, as well as a scientific challenge.

“He fearlessly championed the interests of the citizen over the state and his flash of passion was contagious. How we need the likes of Ian Douglas-Wilson today.”

He is survived by his son, David, two daughters, Joanna and Liz, seven grandchildren and seven great-grandchildren.