Under an agreement between the governments of Australia, New Zealand and Britain the British Phosphate Commission was established on July 1919 to administer the Island of Nauru. 

The valuable phosphate deposits on the island had hitherto been worked by various companies, the most recent before the agreement being the Pacific Phosphate Co. 

As indicated in a lengthy letter dated 26 October 1920 from Alwin R. Dickinson, who had just been appointed Commissioner for the United Kingdom, to Harold Gaze, the General Manager of the Pacific Phosphate Co., it was desired to make the administrative change over as minimal an upheaval as possible. So Gaze and various other Pacific Phosphate Co. personnel working in Australia were offered contracts of employment with the Commission. Similarly, the administrative headquarters was Melbourne, and, to quote from page two of Dickinsons's letter, "The Commissioners have decided that Melbourne shall be the centre for the assembling of the accounts and from which the business of the islands shall be managed." (MP 1174/1, Item 807) But the correspondence did not reflect this change immediately. Although the British Phosphate Commissioners printed letterhead by October 1920 described its Australian Office as 465 Collins Street, Melbourne, the letter from Dickinson to Gaze of that date was addressed to Gaze care of the Pacific Phosphate Company at the same Melbourne address. (Ibid). Gaze himself signed outwards correspondence on behalf of the company right up to the end of December 1920. From 1921 he wrote in his capacity as Chief Representative of the Commission, as he continued to do until after the Second World War. (Who's Who 1953, p. 1055 ) 

The Commissioners also acted as managing agents for the Christmas Island Phosphate Commission [CA 281], a partnership of the Governments of Australia and New Zealand, from commencement of government ownership of the Christmas Island deposits in 1949. 

In addition to managing the phosphate mining operations, they arranged the purchase, shipping and distribution of phosphate supplies from all sources (islands) and managed phosphate stocks in Australia and New Zealand. 

In 1981 arrangements were approved which included the termination of managing the of Christmas Island and the winding up of the Commissioners which ceased operations on 30 June 1981. A company, Phoscom Pty. Ltd. [CA 4205] was set up to carry out the winding up process. The Directors of that company were the four Commissioners from BPC and CIPC.

The Melbourne office of the Commission remained its central
administrative office in Australia. Matters dealt with since this agency was created include general business correspondence to and from the various Commissioners; annual reports and accounts; annual returns of phosphate mined, transported and sold; Japanese occupation of, & subsequent surrender at Nauru and Ocean Islands; employment of Chinese labour on the islands; negotiations and related matters regarding Christmas Island; and the trial of Tai Shek after a murder on Ocean Island in 1949. (MP 1174/1, Items 1112, 1103, 1100, 1108).

The First British Phosphate Commissioners were:-

James Richard Collins (Temporary, 1 July 1920 - 5 January 1921) and Harold Hamilton Benjamin Pope (5 January 1921) representing Australia; 

Alwin Robinson Dickinson representing the United Kingdom; and 

Albert Fuller Ellis (4 May 1921) representing New Zealand.
 

Historical agency address
  1920-by1940: 465 Collins Street, Melbourne
by1940-  1982: 515 Collins Street, Melbourne 
  1982-  1987: 60 Albert Road, South Melbourne
Legislation administered
Commonwealth of Australia Act No. 8 of 1919, Nauru Island Agreement Act 1919; Commonwealth of Australia Act No. 54 of 1932, Nauru Island Agreement Act 1932