Percival Edgar Deane was born on 10 August 1890, the son of a carpenter and master builder.  He was educated at state schools and at University High School, a private institution.  After a period peddling typewriters and working in the office of James Service, a Victorian politician and associate of Alfred Deakin (CP 12), Deane worked as a clerk in the University of Melbourne.  Between the ages of 18 and 23 he was closely associated with various trade and business magazines. 

Deane enlisted as a private in the Australian Imperial Force in September 1914, serving in Egypt and becoming a quartermaster and lieutenant before being invalided in April 1916.  Together with Sir James Barrett, he later wrote The Australian Army Medical Corps in Egypt (1918).

During November 1916 Deane was discharged from the AIF and appointed as Private Secretary to the Prime Minister, W M Hughes.  With Hughes, he attended Imperial Conferences in Britain 1918 and 1921 and was a member and secretary to the Australian delegation at the Versailles Peace Conference in 1919.  In the same year he was apparently an Assistant Secretary to the Imperial War Cabinet and the British Empire Delegation at Versailles.  This is subject to further research. 

In February 1921 Deane was appointed as Secretary and Permanent Head of the Prime Minister's Department (CA 12).  S Murrey-Smith's article on Deane in the Australian Dictionary of Biography (Vol 8, p 261) comments that he was 'unquestionably the most discussed of Federal Government officials' and that his 'status as Hughes' alter ego' made him 'the one everyone wanted to know.'  Deane was also Secretary of the Department of External Affairs [II] (CA 18) from 1921.

Hughes was defeated in 1923. In the same year Deane was investigated by the Royal Commission in connection with Sugar Purchases by the Commonwealth through Mr W E Davies (CA 2408).  He moved to Canberra with the Department in 1927, having accompanied Prime Minister Bruce to the Imperial Conference in London during the previous year.  In 1928 he relinquished his position as Secretary of the Department of External Affairs [II].  In 1929 he relinquished his position with the Prime Minister's Department and became Secretary and Permanent Head of the Department of Home Affairs [II] (CA 24).

That Department was abolished in 1932 and Deane became a member of the War Pensioners Entitlement Appeals Tribunal No 1 (CA 643).  Deane retired to Melbourne on 3 September 1936 and died on 17 August 1946.  

Agency associated with person unregistered

1918-1918: Australian Delegation to Imperial Conference, London -
           Secretary
1919-1919: Australian Peace Delegation, Paris - Secretary and Member
1919-1919: Imperial War Cabinet - Assistant Secretary
1919-1919: British Empire Delegation, Paris - Assistant Secretary