David Finlayson was the son of Robert Finlayson and Margot Finlayson (nee Spencer). He was the husband of Marjorie Olive Innes Finlayson of Feilding, Wellington.

David Finlayson attended King's College, Auckland from 1933-36 and was a School Prefect in School House. He was the editor of the school magazine and later worked on the reporting staff of the Otago Daily Times.

He enlisted in 1940 and served on a coastal defence unit for Fanning Island and was later commissioned for service in Tonga. He resigned his commission in favour of service in the Middle East.

On 24 November 1944 22 Battalion was taken by Fourth Reserve Motor Transport Company's three-tonners away from Fabriano to the north to relieve a British unit on the Lamone River. Their new position was north east of the newly captured town of Forli. The next move was to capture Faenza, which was achieved before Christmas. The Germans were in a strong position, well fortified in Ronco and the advance was slow. The battalion was charged, together with 23 Battalion on their left and the Gurkhas on the right, with clearing the Germans across the river. On 26 November they were patroling the river and its banks when they penetrated a stopbank and were driven back by strong fire and grenades. It appears that Private Finlayson died in this action. AWMM