Brian was born 11th March 1889, the only son of Hugh Cumberland J.P Land Agent & Auctioneer & Jeanie nee Clarke. In 1901 he was at a boys boarding school in Harpenden, but in the 1911 census he is home with his sisters, mother & father at The Lynchets, Hart Hill.

Before joining the Bedfordshire regiment, he passed his exams to become a member of the Auctioneers & Surveyors Institute so he could join the family business who's offices were in Castle Street.

He obtained a 2nd Lieutenancy in the Bedfordshire Territorials in 1911, was promoted to Lieutenant in May 1913 & then Captain on 29th August 1914.

On 17th January 1912 he was initiated into his father's Masonic Lodge of St John The Baptist.

He was a keen sportsman, good at tennis & a well known member of the South Beds Golf Club.

On 6th August 1915 the British & Commonwealth forces opened up a new front on the Gallipoli peninsular with the intention of breaking the deadlock that had set in at Helles & ANZAC. New landings were made in the Suvla Bay area with the idea of taking the surrounding hills & attacking the Turkish Army from the rear & forcing their way to victory.

Captain Cumberland arrived at Suvla Bay with 1/5th Battalion on 12th August 1915. He was killed in action 3 days later, aged 26. He was described by his Battalion CO as a "superb leader". He "called on his company for the last charge up the crest (towards Kidney Hill itself) & in the act of waving them on, he was shot through the head"

He is buried in Azmak Cemetery, Suvla. His father erected a memorial in the Crawley Green Road cemetery.