Burnett William Kann was born at Gayndah, Queensland, on 6 November 1896, to parents Hargen and Louise nee Ottermiller . His father appears to have anglicised his name and was commonly known as as Martin John Kann.
Burnett Kann was working as a labourer when, aged 18, he enlisted in the Australian Imperial Force on 5 October 1915. He embarked with the 15th reinforcements of the 15th Battalion at Brisbane on 28 March 1916, aboard HMAT Commonwealth.
He joined the 15th Battalion in France on 22 December 1916 and also played the Bb Tuba in the 15th Battalion Band. Kann was sick with scabies between 7 April - 7 April 1917, spending time in hospital and rejoining his unit on 20 April 1917. From 29 October to 12 November 1917 , he was on leave in England. He was again granted leave on 19 October 1918 and returned from leave on 4 November 1918 . Afterwards, he remained with the 15th Battalion in France, until he mobilised to return to Australia from France. He left France and embarked for England on 16 April 1919.
Kann returned to Australia aboard HMAT Beltana on 2 June 1919. He married Annie Alison McNamara on 8 August 1925. In 1939, Kann was working as a milkman in Maryborough and relocated with his wife to the Sutherland area of Sydney during the 1950s. He was living in Sydney at the time of the engagement of his youngest son, Burnett William Kann, in 1953. Kann resided in the Wide Bay area of Queensland for most of his life and died at Gayndah on 3 January 1971.