[2][3] Moulden arrived in South Australia with his parents in October 1850.
[1] Moulden was appointed Attorney-General in the John Cockburn Ministry on 27 June 1889, but retired on 19 March 1890, prior to the defeat of the Ministry, owing to his disapproval of some items of their policy.
[1][2] He was a longtime friend of land developer W. H. Gray, and acted as his lawyer, associate in many ventures, and co-executor of his Will.
[4] Moulden was elected to the South Australian Legislative Council on 19 December 1903 for Central District No.
Beaumont Arnold Moulden married Anna Mary Cramond on 25 September 1872; they had four children:[3]