The Department of Home Affairs [III] was established on 20 December 1977 by Executive Council Meeting No. 104 (PSB Minute No. 1977/79), notified in Commonwealth Gazette (No. S289) of 20 December 1977.  
Background notes issued by the Government at the time of the
administrative changes of 20 December 1977 to explain the changes included the following statement concerning Home Affairs [III]:  

 "This department will assume responsibility for the administration
 of the Territory of Cocos (Keeling) Islands, the Territory of
 Christmas Island, Norfolk Island and the Coral Sea Islands Territory
 (from the Department of Administrative Services); national archives
 and museums and support for Department of Administrative Services;
 and Women's Affairs and support for the arts and letters (from the
 Department of the Prime Minister and Cabinet).
 
 Associated bodies for which the Minister for Home Affairs will be
 responsible include the Australian War Memorial, the National
 Library of Australia, the Australia Council, the Australian National
 Gallery, the Australian Film Commission and the Film and Television
 School ......
 
 It is the Government's intention that, in the long term, residual 
 functions of the Departments of the Northern Territory and the
 Capital Territory will be transferred to the Department of Home
 Affairs. With this is mind, administration of the Departments of
 Home Affairs and the Capital Territory will .... be the
 responsiblity of one Minister".
 
The functions of the Department of Home Affairs [III] as formally set out in the Administrative Arrangements Order of 20 December 1977 were:
 
 Administration of Norfolk Island, the Territory of Cocos (Keeling) 
  Islands, the Territory of Christmas Island and the Coral Sea
  Islands  Territory
 Women's Affairs
 Support for the arts and letters
 National archives
 National museums
 
Acts administered by the Department on its creation were:
 
 Australia Council Act, 1975
 Australian Film Commission Act, 1975
 Australian Film Development Corporation Act, 1970
 Australian War Memorial Act, 1962
 Christmas Island Act, 1958
 Cocos (Keeling Islands Act, 1955
 Continental Shelf (Living National Resources) Act, 1968, in so far 
  as it relates to Norfolk Island, the Territory of Cocos (Keeling) 
  Islands, the Territory of Christmas Island and Coral Sea Islands 
  Territory
 Coral Sea Island Act, 1969
 Film and Television School Act, 1973
 Historic Shipwrecks Act, 1976
 National Gallery Act, 1975
 National Library Act, 1960
 Norfolk Island Act, 1957
 Removal of Prisoners (Territories) Act, 1923 in so far as it relates
  to Norfolk Island, the Territory of Cocos  (Keeling) Islands, the
  Territory of Christmas Island and the Coral  Sea Islands Territory.
 
On 1 July 1978, most of the then remaining functions of the
Department of the Northern Territory [II] (CA 1958) were transferred to the Northern Territory Government. The residual function of the Department of the Northern Territory, the "constitutional
development of the Northern Territory of Australia", passed to the Department of Home Affairs [III] under the Administrative
Arrangements Order of 28 September 1978 (Commonwealth Gazette, No S190, 28 September 1978). 

Acts administered by the Minister for Home Affairs, which were added by this administrative change were:  

 Ashmore and Cartier Islands Acceptance Act, 1933
 Darwin Lands Acquisition Act, 1945
 Darwin Reconstruction Act, 1975
 Legislative Assembly of the Northern Territory (Remuneration and 
  Allowances) Act, 1978
 Northern Territory Acceptance Act, 1910
 Northern Territory (Self-government) Act, 1978 except sections 69
  and 70
 Removal of Prisoners (Territories) Act, 1923 in so far as it relates
  to the Northern Territory (except to the extent administered by
  the Attorney-General)
 
The Administrative Arrangements of September 1978 also transferred responsibility for the following act from Home Affairs [III] to the Department of Primary Industry [II] (CA 1960):
 
 Continental Shelf (Living Natural Resources) Act, 1968 in so far as
  it relates to Norfolk Island, the Territory of Cocos (Keeling)
  Islands, the Territory of Christmas Island and the Coral Sea
  Islands Territories.
 
The Department of Environment, Housing and Community Development (CA 1954) was abolished on 5 December 1978 (PSB Minute No 1978/56 of 5 December 1978). The Administrative Arrangements Order of 5 December 1978 (Commonwealth Gazette, No S269, 5 December 1978) described the functions passing to Home Affairs [III] as including:
 
 Leisure, including sport, physical fitness and community
  recreation.  

The enactments passing from the abolished department to Home Affairs [III] were the Australian Heritage Commission Act, 1975 and the National Fitness Act, 1941.
 
The Administrative Arrangements Order of 26 February 1979
(Commonwealth Gazette No. S37, 26 February 1979) transferred
responsibility for the following act from the Department of National Development [II] (CA 2475) to Home Affairs [III]:
 
 Urban and Regional Development (Financial Assistance) Act, 1974 in
 so far as it relates to national estate grants.
 
A referendum on self-government for the Australian Capital Territory was held in November 1978, after agitation for constitutional change. The Government had previously stated its intention to grant self-government to the ACT if this was required, and the Department of the Capital Territory (CA 1477) was to have been absorbed by Home Affairs [III]. A strong vote for the status quo in the ACT Government resulted merely in the replacement of the ACT Legislative Assembly (CA 2027) by the ACT House of Assembly (CA 3035) and the proposed amalgamation of Capital Territory and Home Affairs [III] did not take place.
 
On 3 November 1980 the Department of Home Affairs [III] was replaced by the Department of Home Affairs and Environment (CA 3068) (PSB Minute No 1980/56, Commonwealth Gazette, No S247, 3 November 1980). The new department assumed all the functions of Home Affairs [III], the environment and conservation functions of the former Department of Science and the Environment (CA 2749) and the expositions
function of the Department of Administrative Services [II] (CA 1964). Dr D F McMichael, Secretary of Home Afairs [III], became the Secretary of the new department under the Minister, the Hon R J Ellicott (CP 134).
 
The Annual Report of the Department for 1978-1979 (Commonwealth Parliamentary Paper No 362 of 1979) supplied the following
information about the top structure of Home Affairs [III]:
 
Co-ordination and Management Division:
 Legislation and Law Reform Branch;
 Cultural Affairs Branch;
 Arts Section:
 Film and Library Section;
 Collections and Historical Section
 Management Services Branch;
 Administration of National Estate;
 Projects Branch;
 
Territories Division:
 Sports and Recreation Branch;
 Sports Development Section;
 Recreation and Fitness Section;
 Indian Ocean Territories Branch;
 Cocos (Keeling) Islands Section;
 Cocos (Keeling) Islands Policy;
 Christmas Island Section;
 Island Management and Operations;
 Other Territories Branch;
 Pacific Ocean Territories Section;
 Northern Territory Section;
 Darwin Office;
 Northern Territory Department Recovery
 Uranium
 
Office of Women's Affairs:
 Projects A Section;
 Projects B Section;
 Secretariat to National Women's Advisory Council.
 
The two Divisions and the Office of Women's Affairs were responsible to the Secretary, Dr. McMichael, who was also responsible for the Director of the Australian War Memorial, the Director-General of the Australian Archives and the Director of the Australian Heritage Commission.
 
During the initial period of the Department, management services such as the accounts, personnel and industrial relations sections, were provided by the Department of Administrative Services [II] (CA 1964). This support of the Central Office of Home Affairs [III] ceased by the end of June 1978, but Administrative Services [II] continued to provide management services for the Australian Archives in the states and the Northern Territory, and to the Department's Northern Territory office in Darwin. 
 
Minister of the Department of Home Affairs [III] was:
 
20 Dec 1977 -  3 Nov 1980  : Hon Robert James Ellicott (CP 134)  

Secretaries to the Department were:
 
20 Dec 1977 - 27 Feb 1978  : A R Palmer (acting)
27 Feb 1978 -  3 Nov 1980  : Dr F McMichael (CP 303)
 

Historical agency address
  1977-1978: East Block, Parkes ACT
by1978-1978: Casey House, Rhodes Place, Yarralumla ACT
  1978-1980: CML Building, University Avenue, Canberra City ACT
Legislation administered
Creation: Executive Council Meeting No. 104, (PSB Minute No. 1977/79) of 20 December 1977 
Abolition: Executive Council Meeting No. , (PSB Minute No. 1980/56) of 3 November 1980