When the Commonwealth was inaugurated in 1901, it became necessary to have in London an officer to pay outstanding accounts, arrange and supervise purchases etc. It was therefore arranged within the states that the Agents-General in London (acting with shared responsibility) would receive communications and act on behalf of the Commonwealth (1).

This arrangement was in force until c1905 when the Agents-General decided to form themselves into a committee to handle jointly matters of Australian interest.

On 20 February 1906, the Prime Minister, Alfred Deakin, informed the Governor-General that it had been decided to establish a Commonwealth Office in London to deal with remittance on behalf of the Commonwealth and to supervise the expenditure in connection with Defence stores intended for Australia. He went on to advise the Governor-General that Captain Robert (later Sir) Muirhead Collins, CMG, Secretary, Department of Defence, had been selected to take charge of the new Office (2).  Captain Collins arrived in London in April 1906 and was generally recognised as the representative of the Commonwealth.

On 13 December 1909, assent was given to 'An Act to provide for the Office of High Commissioner of the Commonwealth in the United Kingdom' (No 22 of 1909). The Right Honourable Sir George Houston Reid, PC, KC, MG was appointed High Commissioner on 22 January 1910 (3).

Captain Collins continued to serve in the subordinate post of Official Secretary until his retirement in 1917.

On 28 October 1966, under the provisions of Commonwealth Act No 56 of 1966, the official title of the High Commissioner was amended to 'High Commissioner for Australia'. Since the Department of Foreign Affairs assumed responsibility for the Office, departmental correspondence, gazettals etc have referred to the position as 'Australian High Commission, London'. However, there does not appear to have been any formal action taken to change the name of the Office.

The foundation stone of Australia House was laid by King George V on 24 July 1913 and the building opened by the King on 3 August 1918. The cost of the land, plus the existing Victoria Building on the site was 379,756 pounds. The cost of the new building, plus furniture bought from Australia was 450,000 pounds.

Up to the commencement of World War II, the building contained all the staff of the High Commission. The Service Branches then moved to other office space in London. In 1966, a long lease was taken on Canberra House, 100 metres from Australia House in Maltravers Street and by mid-1976 all staff were accommodated in this building.

Responsibility for the Office rested with the Department of External Affairs [I] (CA 7) until the latter's abolition in 1916 when the Prime Minister's Department (CA 12) was made responsible for the administration of the High Commissioner Act.

The situation again altered in 1921 with the creation of the Department of External Affairs [II] (CA 18) which, as shown in the Administrative Arrangements Order of 1923, functioned as a joint department with Prime Ministers, under a single Secretary, Mr P E  Deane, and a single Minister, Bruce, who was Prime Minister and Minister for External Affairs.

In 1923 and 1925, the High Commissioner's Office appears to have been under External Affairs. External Affairs [II] was listed separately in the Administrative Arrangements Order in 1932 but the responsibility for the High Commissioner's Office rested solely with the Prime Minister's Department which maintained this role until the abolition of the Department on 12 March 1971. The principal successor department, Prime Minister and Cabinet (CA 1401), inherited the High Commissioner Office function.

In November 1972, the High Commission (United Kingdom) Act was transferred to the auspices of the Department of Foreign Affairs (CA 1382).

In 1973, the new Labor Government passed the High Commission (United Kingdom) Act Repeal Act (4) which passed the administration of the High Commission to the Public Service Act. This placed the administration of the High Commission on the same basis as all other diplomatic missions, indicating that Australia's relations with Britain were no longer to be regarded as different in kind from diplomatic relations with other countries.

The role of the High Commissioner as set out under the 1909 Act which established the position was to:

     (a) act as representative and resident agent of the Commonwealth
         in the United Kingdom, and in that capacity exercise such
         powers and perform such duties, as are conferred upon and
         assigned to him by the Governor-General;
     
     (b) carry out such instructions as he received from the Minister
         respecting the commercial, financial, and general interests
         of the Commonwealth and the States in the United Kingdom and
         elsewhere. (5)

Australian Government policies are expressed to the United Kingdom through the High Commissioner or his staff. This involves consultation between the High Commission and United Kingdom Ministries on all aspects of official relations between the two Governments, eg foreign affairs, defence, trade, immigration, economic relations, communications, etc.

The position of Deputy High Commissioner was created by the Statutory Rules made under the Act on 6 March, 1946 (6). The position, responsible for the efficient working of the High Commission, was a First Division Officer of the Commonwealth Public Service and is equivalent to a permanent head of a Department of State.

'The Deputy High Commissioner is usually appointed from amongst the most senior members of the Australian Public Service... He acts in the place of the High Commissioner whenever it may be necessary. He may be required to lead or otherwise take part in delegations on trade matters, to represent Australia at international conferences, to conduct loan negotiations or to represent the Government at official functions.' (7)

Also in 1946, an Australian Government Trade Commissioner was appointed to the London post.  The Office of Trade Commissioner was established to encourage and facilitate the efforts of Australian exporters to exploit marketing opportunities in the United Kingdom.

The organisation of the Office of the High Commissioner falls into two main groups:

     (a) the central administration, under the control of the
         Official Secretary; and
     
     (b) the representatives of the Defence Services, Departments,
         Boards and Authorities, all of whom are responsible to the
         High Commissioner.

Central Administration -

the Official Secretary is the general administrative head, chief accounting officer and chief security officer and deals with enquiries from the responsible Minister, assists Departmental representatives when in London, undertakes enquiries for, and, pertaining to, Departments not represented in London and maintains generally a close relationship with United Kingdom Ministries, representatives of other countries and other organisations in London. 
In 1962, Central Administration had the following sections:
     
      1. Assistant Official Secretary;
      2. Education Liaison Officer;
      3. Chief Procurement Officer, Procurement Section;
      4. Administrative Officer, Staff Section;
      5. Superintendent of Buildings, Control Section;
      6. Reception Officer;
      7. Hostess;
      8. Chief Finance Officer, Accounts Section;
      9. Travel Section;
     10. Cables Section;
     11. Central Registry;
     12. Social Worker; and
     13. Repatriation and Social Service Pensions.

Departments not directly represented at this time were:

   (a)  Attorney-General's;          (b)   Railways;
   (c)  Interior;                    (d)   Labour and National 
                                           Service;
   (e)  National Development;        (f)   Shipping and Transport;
   (g)  Territories; and             (h)   Works.

Representatives of the Defence Services, Departments, Boards and Authorities -

The officers, representing most Australian Departments and Authorities, have the function of making their specialized knowledge available to the High Commissioner, eg in any negotiations in which he may be engaged, 'representing their Departments views at the official level to the United Kingdom Departments and Authorities, provide a flow of information on technical processes, advise on the technical aspects of departmental stores requirements and assist officers on short visits both in planning their itineraries and in meeting those organisations and persons who will best provide the knowledge which they seek.' (8)

In 1962, the following bodies were represented:

     1. Defence Services - Air, Army, Navy and Defence 
         (Joint Services Staff);
     2. Departments - 
         Civil Aviation;
         Customs and Excise;
         External Affairs;
         Health;
         Immigration;
         Postmaster-General;
         Supply; and
         Treasury.
     3. Boards etc - 
         Australian News and Information Bureau;
         Taxation;
         Auditor-General;
         Australian Atomic Energy Commission;
         CSIRO;
         National Library of Australia;
         Public Service Board; and
         Snowy Mountains Hydro-Electric Authority..

In 1977, the list of Departments represented were:

        Administrative Services (Australian Information Service,
        National Library);
        National Resources (Australian Atomic Energy Commission);
        Attorney-General's;
        Prime Minister and Cabinet (Auditor-Generals, Public Service 
        Board);
        Business and Consumer Affairs (Customs);
        Science (CSIRO);
        Defence (ADS, Air, Army, Navy);
        Finance;
        Foreign Affairs;
        Health;
        Immigration and Ethnic Affairs;
        Productivity;
        Overseas Trade;
        Transport; and
        Treasury (Australian Taxation Office, Overseas Economic
        Relations Division).

Note that 'Capital Designs: Australia House and Visions of an Imperial London' by Eileen Chanin (Australian Scholarly, 2018) covers how Australia's first mission was conceived, designed and built.

The following is a list of High Commissioners appointed since the foundation of the High Commission in London to the mid 1970s:

(22 Jan) 1910-1916 (Jan 10):  Sir George Houston Reid, PC, KC, MG (9)
(22 Jan) 1916-1921 (Apr 21):  The Right Honourable Andrew Fisher (10)
(11 Nov) 1921-1927 (May 10):  The Right Honourable Sir Joseph Cook,
                              PC, GCMG (11)
(11 May) 1927-1932 (May 10):  Major-General the Honourable Sir 
                              Granville de Laure Ryrie, KCMC, CB, VD
                              (12)
(Sept) 1932-1933 (Oct 6)   :  The Right Honourable Stanley Melbourne 
                              Bruce (appointed as Resident Minister)
                              (13)
(7 Oct) 1933-1945 (Oct 6)  :  The Right Honourable Stanley Melbourne
                              Bruce (14)
(7 Oct) 1945 - 1946 (Jan)  :  H V Evatt (appointed as Resident
                              Minister) (15)
(Jan) 1946-1946 (Aug 14)   :  The Right Honourable John Albert
                              Beasley (appointed as Resident
                              Minister) (16)
(15 Aug) 1946-1949 (Sept 2):  The Right Honourable John Albert
                              Beasley (17)
(19 Apr) 1950-1951 (Apr 19):  The Honourable Eric J Harrison (18)
(21 Jun) 1951-1956 (June 20):  The Honourable Thomas Walter White, 
                              KBE, DFC, VD (19)
(25 Oct) 1956-1964 (Oct)   :  The Right Honourable Eric J Harrison, 
                              KCMG, KCVO (20)
(25 Oct) 1964-1972 (Dec)   :  Sir Alexander Downer (21)
(Dec) 1972-1975 (Jan 31)   :  Mr J I Armstrong (22)
(1 Feb) 1975-1977 (Mar)    :  Sir John Bunting (23)
(Mar) 1977-1980            :  Mr Gordon Freeth (24)
      1981-1982            :  J Plimsoll (25)
      1983-1986            :  A R Parsons
      1987-1991 (May)      :  D McClelland
(Jun) 1991-1994 (Aug)      :  R J Smith
(Sep) 1994-1998 (May)      :  N Blewett

References:

 1. CRS A33, Vol 10, pp 373, 511, 713-4
 2. CRS A32, Vol 4, pp 277-278
 3. Commonwealth of Australia Gazette, No 5 22 Jan 1910, p 48 
 4. Commonwealth of Australia Acts, No 156 of 1973, High
    Commissioner (United Kingdom) Act Repeal Act 1973
 5. Commonwealth of Australia Acts, No 22 of 1909, High Commissioner 
    Act 1909
 6. Australia, High Commissioner's Office 'The organisation and 
    functions of the High Commissioner's Office, London' March 1962 
   (Unpublished draft), p 5
 7. ibid, p 2
 8. ibid, p 2
 9. Commonwealth of Australia Gazette, No 5, 22 Jan 1910, p 48 
10. Commonwealth of Australia Gazette, No 56, 11 May 1916, p 1070 
11. Commonwealth of Australia Gazette, No 91, 24 Nov 1921, p 2229 
12. Commonwealth of Australia Gazette, No 45, 5 May 1927, p 87 
13. Australian Encyclopaedia, Vol 1, p 315
14. Commonwealth of Australia Gazette, No 56, 12 Oct 1933, p 1401 
15. Australian Encyclopaedia, Vol 1, p 315
16. op cit
17. Commonwealth of Australia Gazette, No 150, 15 Aug 1946, p 2206 
18. Australian Encyclopaedia, Vol 1, p 315
19. Commonwealth of Australia Gazette, No 47, 5 July 1951, p 1684 
20. Commonwealth of Australia Gazette, No 63, 1 Nov 1956, p 3295 
21. Sydney Morning Herald, 3 June 1970
22. subject to research
23. Prime Minister's Press Statement, No 309, 23 Aug 1974
24. Minister of Foreign Affairs News Release, 20 Feb 1977
25. Commonwealth Government Directory, years 1977-1995

Historical agency address

1910-1917 : 72 Victoria Street, Westminster
1918- : Australia House, The Strand

Legislation administered

Creation: Commonwealth of Australia Acts, No 22 of 1909 
          High Commissioner Act 1909 
          Commonwealth of Australia Act No. 156 of 1973 
          High Commissioner (United Kingdom) Act Repeal Act 1973     
          Commonwealth of Australia Act No. 21 of 1973 
          Public Service Act 1973