In 1917 the Australian Government introduced policies to restrict importation of fully manufactured motor cars to encourage the country's nascent automotive body building industry.

In 1919 Edward (as managing director) and his father founded a company Holden's Motor Body Builders with a factory at 400 King William Street[1] later occupied by A. G. Healing Ltd.[2] In 1923, following the signing of an exclusive agreement in Detroit with General Motors by Edward Holden, a new factory was set up at 879–895 Port Road, Cheltenham, employing the latest in production line technology.

In October 1929 the plant closed temporarily for lack of continuous work, and in January 1930 Holden set out for the United States to discuss amalgamation with General Motors.

The profits from army canteens, which were immense, initially went to improve camp facilities[4] and the surplus of around £2,000,000 realised by the end of the war was distributed by the Australian Military Forces Special Benefits Committee to organisations whose membership was restricted to service personnel.

[7] In 1935 he was elected to the Central District No.2 seat in the Legislative Council of South Australia made vacant by the death of Labor's William Humphrey Harvey.