[6][7] The High Commission of Australia in London is Australia's oldest diplomatic posting, and was created through the passage of the High Commissioner Act 1909 on 13 December 1909, which established the role as appointed by the Governor-General and defined that they would "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 [and] carry out such instructions as he receives from the Minister respecting the commercial, financial, and general interests of the Commonwealth and the States in the United Kingdom and elsewhere.

[9] The new act altered the status of the High Commission to one of equality with all other bilateral posts, in recognition of the fact that Australia's relationship with the United Kingdom had changed.

[5] Four of Australia's early prime ministers served terms as High Commissioner after leaving office: Reid, Fisher, Cook and Bruce.

From 1910, the first high commissioner, Sir George Reid, rented the residence of John Henniker Heaton at 33 Eaton Square, Belgravia.

[12][13] In 1927, the government of Prime Minister Stanley Bruce acquired the lease of 18 Ennismore Gardens in Knightsbridge, from the Earl of Listowel (and succeeding Lord Castlemaine as lessee), a four-storey 1858 terrace house, as the residence for high commissioner Sir Granville Ryrie.

[27][28] Stoke Lodge was originally built in 1838 by Robert Thew, a major of artillery in the East India Company, and in 1851 was the residence of Italian opera singer, Giulia Grisi.