He was the founder chairman of Wellington History Group and edited 28 issues of the group's magazine, as well as giving countless talks to clubs, societies and schools.
In October 2020 he was honoured with the symbolic award of the first ever Key To Wellington by Wellington Town Council, in recognition of his decades of promoting and researching the town's history.
Neil Clarke, current chairman of the history group, said: "Allan was undoubtedly the acknowledged authority on the history of Wellington and he made a tremendous contribution to the promotion of local history in the area. I was privileged to proof-read his magnum opus ‘Histories of Wellington, Shropshire’, published last year.
"He will be greatly missed."
Allan helped many with family research, contributed to film scripts, radio and TV programmes and newspaper articles and was awarded a town council plaque in 2010 for his services to the town.
He is survived by widow, Dorothy, whom he married in 1994, and two children from a previous marriage, Caroline and Tim.
There will be a private family burial at Wellington cemetery on Friday, December 30, followed at 10.45am that day by a thanksgiving service at Wellington Methodist Church.
Allan wrote over 40 books on subjects including Wellington’s pubs and breweries, the Great War and The Wrekin. He was instrumental in creating history boards in Market Square, showing the location of the 17th century Market House, and instigated an archaeological dig in Walker Street which produced evidence of medieval tanning and horn-working.
He also identified the oldest known building in Wellington as part of Edgbaston House.
Allan lived in later life in Priorslee but was born and grew up in Wellington, his family having lived in the area for well over 250 years.
He began collating information on Wellington when he was 15 and it was to lead to 55 years of research before he called it a day in early 2020. At the time the then town mayor Anthony Lowe said he had become "a Wellington institution in his own right".
His researches were characterised by a painstaking desire to ensure accuracy, a lasting legacy from a stinging comment by his history teacher on a school report that he was "interested and intelligent but blithely inaccurate".
In his campaigning he sought to prevent aspects of Wellington's heritage being carelessly lost, even down to successfully restoring the missing apostrophe in the Prince's Street street sign. The street had, he pointed out, been given that name in 1861 as a memorial to Prince Albert, Queen Victoria’s beloved husband, who had just died.
Another triumph in a similar vein was getting Greenman Close to become Green Man Close to reflect its origins as the site at Mill Bank of the Green Man pub which was demolished in 1999.
Allan went to Wellington Grammar School and worked for the Inland Revenue, which is how he met Dorothy who also worked for the Inland Revenue and had moved down from Hamilton in Scotland in the 1980s.
Dorothy said: "He was certainly a one-off. You couldn't ask him a question – everything to Allan was a story, and if you asked him a question you got the history from A to Z, and the answer was in there."
She said having finished his last Wellington book he had been working on a compilation of his family history.
He died in Severn Hospice in Telford on December 10 after being taken to hospital last month, where a scan showed he had cancer.
A key event had proved the catalyst for a lifetime uncovering Wellington's past.
When he was 15, his father Leslie pointed out a headstone in All Saints’ parish churchyard. It recorded the deaths of four Frost children by explosion in March 1839.
"They were the offspring of my great-great-grandfather who ran a coal mine at Newdale," Allan was to recall.
“All my father could tell me was the family story handed down over the years. He suggested I try to find out exactly what happened. I soon found out that the story differed from official reports. So, armed with the ‘blithely inaccurate’ stigma, I made a promise to myself that I would do my best to avoid unsupported speculation.
“Then I decided to find out more about the lives of my ancestors, and the history of Wellington.”