Official records show that Bertram died on October 26th 1917 although this may be the day on which he was reported missing. The Shaftesbury Grammar School magazine gives some details: "Bertram Keast was shot in the left arm on the Paschendale front, on October 26th, 1917, and taken prisoner." According to this account he was transported to Germany and died there on November 5th. He was buried in the civilian churchyard at Essen.
Bertram was awarded the Victory and British War medals and his name appears on the Tyne Cot Memorial (Panel 38 to 40). He is remembered on the Park Walk War Memorial, on the Holy Trinity Memorial, now in St. Peter's Church and on the Shaftesbury Grammar School memorial in Shaftesbury School. His widow Kate remarried Ernest Ridgeway in 1926.
The June 1917 edition of the Shaftesbury Grammar School magazine mentions a donation by Bertram's father: "A framed list of the names of over 160 boys on active service, now adorns our Schoolroom wall. It was written by Mr. S.J. Keast, and presented by him to the School. We offer him our grateful thanks for his most artistic production, which is one more proof of the great interest he always takes in all that concerns the School." In Gold Hill Museum there is a hand written list of Shaftesbury Grammar School old boys who served in the forces, updated throughout the war, but it is not known if this is the work of Mr. Keast. Bertram's name was included and an asterix can be seen next to his name, indicating that he had died.
Shaftesbury Grammar School Magazine, March 1919
Shaftesbury Grammar School Magazine, June 1917