Dunn was born in Clitheroe, in Lancashire. He was married to Ellen Pawle in 1885 and they had one son and a daughter.
By profession he was an auctioneer and surveyor, a Fellow of the Surveyors' Institution. He was a well-known figure in the business and civic life of the City of London. He was an Alderman of the City of London and Sheriff in 1906–1907. He was Lord Mayor of London in 1916–1917.[1] He was also a Liveryman of several of the City Guilds and an officer in the Territorial Force.[2]
He was knighted in 1907 [1] and created a baronet in 1917.[3][4] He was succeeded in the baronetcy by his son John Henry Dunn, who was only located many years later working at a coal mine near Barnsley.[5]
