The Department of the Northern Territory [I] was created on 19 December 1972 (notified in Commonwealth of Australia Gazette, No 131, 20 December 1972). The Department was responsible for the administration of the Northern Territory of Australia and the Territory of Ashmore and Cartier Islands. It dealt with the following principal matters:
 
 Urban development and town planning
 Transport planning
 Lands
 Local government, community services and housing
 Forest, fisheries, wildlife, and National Parks
 Animal industry and agriculture
 Mines
 Water resources
 
The Department of the Northern Territory [I] administered the following legislation:
 
 Ashmore and Cartier Islands Acceptance Act 1933-1938
 Darwin Lands Acquisition Act 1945
 Northern Territory Acceptance Act 1910-1952
 Northern Territory (Administration) Act 1910-1972
 Petroleum (Ashmore and Cartier Islands) Act 1967
 Petroleum (Submerged Lands) Act 1967-1968, insofar as it relates to 
  matters concerning the area adjacent to the Northern Territory of  
  Australia and the area adjacent to the Territory of Ashmore and 
  Cartier Islands
 Petroleum (Submerged Lands) (Exploration Permit Fees) Act 1967,
  insofar as it relates to matters concerning the area adjacent to
  the Northern Territory of Australia and the area adjacent to the
  Territory of Ashmore and Cartier Islands
 Petroleum (Submerged Lands) (Pipeline Licence Fees) Act 1967,
  insofar as it relates to matters concerning the area adjacent to
  the Northern Territory of Australia and the area adjacent to the
  Territory of Ashmore and Cartier Islands
 Petroleum (Submerged Lands) (Production Licence Fees) Act 1967,
  insofar as it relates to matters concerning the area adjacent to
  the Northern Territory of Australia and the area adjacent to the
  Territory of Ashmore and Cartier Islands
 Petroleum (Submerged Lands) (Registration Fees) Act 1967, insofar as
  it relates to matters concerning the area adjacent to the Northern 
  Territory of Australia and the area adjacent to the Territory of 
  Ashmore and Cartier Islands
 Petroleum (Submerged Lands) (Royalty) Act 1967, insofar as it
  relates to matters concerning the area adjacent to the Northern
  Territory of Australia and the area adjacent to the Territory of
  Ashmore and Cartier Islands
 Removal of Prisoners (Territories) Act 1923-1968, in relation to 
  prisoners sentenced in the Northern Territory of Australia or the 
  Territory of Ashmore and Cartier Islands.
 
As of February 1973, the Department was based in Darwin and structured as follows:
 
 Lands and Community Development Division
 Resource Development Division
 Special Projects Branch
 Managements Services Branch
 
By November the same year the structure had changed to incorporate a Social and Commercial Affairs Division in place of the Special Projects Branch and a Management, Legislation and Planning Division in place of the Management Services Branch.
 
Agreement was reached between the Minister for Aboriginal Affairs, Senator Cavanagh, and the Minister for the Northern Territory, that the social welfare functions previously carried out within the Department of Aboriginal Affairs would be transferred to the Department of the Northern Territory [I]. The Community Welfare Section became part of the Social and Commercial Affairs Division of the Department of the Northern Territory from 25 February 1974. However, this change was not reflected in any of the Administrative Arrangements Orders during the life of the Department of the Northern Territory [I].
 
In the Administrative Arrangements Order of 2 October 1974,
responsibility for Section 21 of the Northern Territory (Administration) Act (dealing with the Aboriginal Benefits Trust Fund) passed to the Department of Aboriginal Affairs (CA 1476).
 
An Australian Capital Territory Secretariat (CA 1534) of the Department was located in Canberra and by March 1974, District Offices had been established at Alice Springs, Katherine, Nhulunbuy, and Tenant Creek. Prior to the creation of the Department, control of the Northern Territory rested with the Minister for the Interior and the Department's Northern Territory Administration based in Darwin had its own divisional structure, headed by the Administrator.
 
On 15 June 1973 the Minister (Mr Kep Enderby) announced that the Administrator, Mr F C Chaney, would relinquish the office of
Administrator as from 1 August 1973, recognising an inconsistency in having a separate Administrator, charged under the Northern Territory (Administration) Act with the duty of administering the Government of the Territory alongside a Departmental structure with similar
responsibilities. The Secretary of the Department, Mr T A O'Brien, was appointed acting Administrator with the power to assent to legislation reserved for the pleasure of the Governor-General. On 4 December 1973, Mr J N Nelson was appointed Administrator, with the delegation to assent to ordinances of the Legislative Assembly.
 
The Northern Territory (Administration) Act 1974 established the Northern Territory Legislative Assembly; the Assembly met for the first time on 20 November 1974 and was responsible to the Administrator.  

The following were Ministers of the Department:
 
19 Dec 1972 - 19 Oct 1973   : Hon Keppel Earl Enderby
19 Oct 1973 -  6 Jun 1975   : Hon Dr Rex Alan Patterson
 
The following were Secretaries of the Department:
 
19 Dec 1972 -  9 Jan 1973   : George Warwick Smith
09 Jan 1973-06 Jun 1975  : T. A. O'Brien
 
The Department of the Northern Territory [I] was abolished on 6 June 1975 (notified in Commonwealth of Australia Gazette, No S 104, 6 June 1975). The functions of the Department, together with some functions of the Department of Northern Development (CA 1483) were taken over by the newly created Department of Northern Australia (CA 1889).

 
References
 
1. Department of Aboriginal Affairs Report for the period December   
   1972-June 1974, Commonwealth Parliamentary Paper No 299 of 1974,
   p 2 and Department of Aboriginal Affairs Media Release, 22
   February 1974.
Historical agency address
1972-1973: Qantas House London Circuit, Canberra City ACT
1973-1975: Mitchell St, Darwin NT
Legislation administered
Creation: Executive Council Meeting No.55 (PSB Minute No.48) of 19 December 1972
Abolition: Executive Council Meeting No.58 (PSB Minute No.23) of 6 June 1975