The Department of Air was created (by Executive Council Minute 72, Prime Minister's Department Minute Number 167) on 13 November 1939
(Commonwealth of Australia Gazette, No 134, 14 November 1939, p 2391). The first Minister of the Department was the Honourable James Valentine Fairbairn (appointment notified in Commonwealth Gazette, No 134, 14 November 1939, p 2391).
 
Before the war, Air Force administration was carried on under the Department of Defence [II] (CA 19). The Air Board - consisting of the Chief of the Air Staff (Chairman), the Air Member for Personnel, the Air Member for Supply and the Finance Member - was responsible for the control and administration of the Royal Australian Air Force, subject to the Regulations under the Air Force Act 1923 and to the policy laid down by the Minister for Defence.
 
On 13 November 1939, the separate Department of Air was established and the basic administrative and financial functions in relation to the Air Force previously carried on by civilian staff in the Department of Defence [II] were taken over by the new Department. These functions included executive functions previously discharged by the Defence Secretariat, clerical work associated with the Air Board and the Branches of the Chief of the Air Staff, the Air Member for Personnel, and the Air Member for Organisation and Equipment, the work of the Finance Branch (Air) and the internal audit of Stores (Air Services). The Air Board was continued, but its control became subject to the policy laid down by the Minister for Air in place of the Minister for Defence.
 
On 13 March 1940, the Air Board was re-organised and reconstituted with the following members:
 
 Chief of the Air Staff (Chairman)
 Air Member for Organisation and Equipment
 Air Member for Personnel
 Director-General of Supply and Production
 Finance Member
 
The Secretary, Department of Air, was ex-officio, also a member of the Board. In January 1941, a Business Member was appointed to the Air Board and the Business Manager's Branch was established.
 
On 9 April 1941, the Meteorological Branch of the Department of Interior [II] was transferred from that Department to the Department of Air and was placed in the Branch of the Chief of the Air Staff, where it was partly staffed by enlisted personnel and partly by permanent and temporary civilian staff.
 
Between October 1940 and October 1942 Area Finance Offices were opened in Sydney, Melbourne, Brisbane, Adelaide and Perth. In June 1942, on the re-organisation of the Service branches of Air Force Headquarters, the Air Board was again reconstituted with the following members:

 Chief of the Air Staff (Chairman)
 Air Member for Personnel
 Air Member for Engineering and Maintenance
 Air Member for Supply and Equipment
 Finance Member
 Business Member

The Secretary, Department of Air, was an ex-officio member. During the Second World War (particularly in 1943-45 owing to the difficulty of obtaining civilian staff) Air Force personnel were used in branches and directorates in which the work was previously done by civilians.  This was most marked in the Finance Branch and the Aeronautical Inspection Directorate of the Branch of the Air Member for Engineering and Maintenance.
 
In December 1945, the Service Branches of Air Force Headquarters were again re-organised but no change was made in the constitution of the Air Board. Under this re-organisation, two new Directorates of Pay Administration and Unit Accounts were included in the Finance Branch. The other changes in organisation involved no material alteration in the civilian staffing of the Department.
 
The Branches and Directorates of the Department at RAAF Headquarters as at 1945 were as follows:
 
SECRETARIAT:
 Secretarial Staff
 Secretary (Air Board) Regulations and Orders
 Staff Section
 Registry
 Directorate of Public Relations
 
BRANCH OF THE CHIEF OF THE AIR STAFF:
 Directorate of Air Staff Policy
 Operational Research Section
 Directorate of Organisation
 Directorate of Staff Duties
 War History Section
 Directorate of Telecommunications and Radar
 Directorate of Meteorological Services
 
BRANCH OF THE AIR MEMBER FOR PERSONNEL:
 Office of the Judge-Advocate-General
 Directorate of Personal Services
 Airmen's Records Section
 Casualty Section
 Directorate of Postings
 Directorate of Training
 Directorate of Educational Services
 Directorate of Manning
 Director of Medical Services
 Directorate of Dental Services
 Directorate of Air Training Corps
 Directorate of WRAAF
 AMP Registry
 
BRANCH OF THE AIR MEMBER FOR SUPPLY & EQUIPMENT:
 Directorate of Equipment
 Directorate of Supplies and Services
 RAAF Canteen Services
 Directorate of Equipment Administration
 Directorate of Transportation and Movements
 Directorate of Works and Buildings
 Directorate of Disposals
 Directorate of Air Force Postal Services
 
BRANCH OF THE AIR MEMBER FOR ENGINEERING & MAINTENANCE:
 Directorate of Technical Service
 Directorate of Aeronautical Inspection
 Directorate of Repair and Maintenance
 Directorate of Armament
 Inventions Section
 
FINANCE BRANCH:
 Central Office
 Directorate of Pay Administration
 Directorate of Unit Accounts
 
BUSINESS MEMBER'S BRANCH:
 Internal Audit of Stores Section
 Area Finance Offices: Sydney, Melbourne, Brisbane, Adelaide and 
  Perth
 
This information was taken from the Committee of Review into the Civil Staffing of Wartime Activities (also known as the Pinner Committee). The administrative structure of the Department after 1945 is subject to further research.
 
The principal matters dealt with by the Department at the time of its abolition were:
 
 Air Defence
 Organisation and Control of Air Forces of the Commonwealth
 (Commonwealth Directory 1972, p 37)
 
The following legislation was administered by the Department at the time of its creation:
 
 Air Force Act 1923
 (Commonwealth Gazette, No 153, 30 November 1939, p 2636)
 
By 1972 it was responsible for the following Acts:
 
 Air Force Act 1923-1965
 Defence Act 1903-1970, in relation to the organisation and control
  of the Air Force
 Royal Australian Air Force Veterans'
 Residences Act 1953-1965
 Services Trust Funds Act 1947-1950, Part VI
 War Service Estates Act 1942-1943, insofar as it applies to the Air
  Force
 (Commonwealth Gazette, No 131, 20 December 1972, p 2)
 
With the coming to power in December 1972 of the Australian Labour Party, there were no new immediate administrative changes for this department. The new Labour Minister for Air was the Honourable Lance Herbert Barnard MP. He was also the Minister for Defence, Navy, Army and Supply. On 30 November 1973, the Department of Air was abolished in pursuance of section 64 of the Constitution and the office of the Secretary to the Department of Air was abolished in pursuance of the Public Service Act by Executive Council Minute No 65 (PSB Minute No 79) of 30 November 1973, notified in Commonwealth Gazette, No 183, 30 November 1973, p 1.
 
The functions of the Department of Air passed to the newly created Air Office (CA 1567) in the Department of Defence III (CA 46).
 
Ministers for Air were:
 
13 Nov 1939 - 13 Aug 1940  : Hon James Valentine Fairbairn (CP 124)
14 Aug 1940 - 28 Oct 1940  : Hon Arthur William Fadden
28 Oct 1940 -  7 Oct 1941  : Hon John McEwen (CP 47)
 7 Oct 1941 - 19 Dec 1949  : Hon Arthur Samuel Drakeford (CP 139) 
19 Dec 1949 - 11 May 1951  : Hon Thomas Walter White (CP 145) 
11 May 1951 - 17 Jul 1951  : Hon Philip Albert Martin McBride
17 Jul 1951 -  9 Jul 1954  : Hon William McMahon
 9 Jul 1954 - 24 Oct 1956  : Hon Athol Gordon Townley
24 Oct 1956 - 29 Dec 1960  : Hon Frederick Meares Osborne
29 Dec 1960 - 22 Dec 1961  : Senator the Hon Harrie Walter Wade
22 Dec 1961 - 27 Jul 1962  : Hon Leslie Harry Ernest Bury (CP 34) 
 2 Aug 1962 - 10 Jun 1964  : Hon David Eric Fairbairn (CP 124) 
10 Jun 1964 - 28 Feb 1968  : Hon Peter Howson
28 Feb 1968 - 13 Feb 1969  : Hon Gordon Freeth (CP 45)
13 Feb 1969 - 12 Nov 1969  : Hon George Erwin
12 Nov 1969 -  5 Dec 1972  : Hon Thomas Drake-Brockman
 5 Dec 1972 - 30 Nov 1973  : Hon Lance Barnard (CP 99)
 

Historical agency address
  1939-by1959: Victoria Barracks, St Kilda Road, Melbourne
by1959-by1961: Administrative Building, Canberra, ACT
by1961-  1973: Russell Offices, Canberra, ACT
Legislation administered
Creation: Executive Council Minute No. 72 (P.M. Minute No. 167) of 13 November 1939.
Abolition: Executive Council Minute No. 65 (P.S.B. Minute No. 79) of 30 November 1973.