He was born in Kilmacolm in Renfrewshire in 1931 and lived in Camden for more than 50 years. He is very much missed and fondly remembered for lighting up a room with his humour, eloquence, erudition and passion.

He grew up one of five children on the golf course where his father, Thomas, was greenkeeper.

Gil and his family’s lives changed when their mother, Jean, had an accident at home. She spent years recovering in hospital, and their father fell ill from overwork, which affected Gil deeply.

After leaving school, he served as a military private secretary to Field Marshal Montgomery in Paris during his national service. Gil left for London in 1953 and lived there the rest of his life.

He married twice, to Helen Morton and Anita van de Vliet, and also had relationships with Ruth, and Kenteas Brine.

His children with Helen, Joe and Sam, and with Kanteas, Zachary, survive him.

He met his first wife, psychologist Helen Morton, in 1966 and they lived in West Hampstead. Gil worked as an interviewer and research consultant and was a mature student at Sussex University when his first book was commissioned.

His best-known book, The Twentieth Century Book of the Dead, was published in 1972 to great acclaim. It focused on death in conflict in the century, and featured a fictional account of one individual death: the unknown soldier or civilian. His second book, Lucifer: a Journey Through Hell-Gate, was published in 1978. He later wrote several others, including The Shock of Mortality, and Adventures in Love.

He later separated from Helen and fell in love with another writer, Ruth, who passed away. He then met actress, TV and film producer Kenteas Brine. They lived together in South Hampstead and had a son, Zachary, in 1981. Gil loved being a father and was always very proud of his three sons. Years later, when he first found out he was to become a grandfather, he leapt in the air with joy.

In the early 1990s, he met and married the journalist Anita van de Vliet, originally from South Africa, and they lived in St Augustine’s Road. They visited South Africa and began to research the politics of the post-Apartheid era.

In his late 70s, he suffered a stroke, but his brilliant mind never deserted him and he adjusted to his new circumstances with great determination and grace.

He was a lifelong Labour supporter, voracious reader, Guardian subscriber and a frequent contributor to their letters page.

Gil is survived by his older brother Tony and younger sisters Anne and Sheena, his wife Anita and her daughter Miranda, his sons Joe, Sam and Zac, his eight beloved grandchildren, Lucia, Luke, Tai, Jake, Daisy, Ariella, Matilda and Alice, and many nieces, nephews and cousins. He was greatly loved and will be missed by many people.

The funeral service will be held at 11m on Saturday at Islington and St Pancras Cemetery and is open to friends and anyone who knew and loved Gil.