Admiral Percival Henry Hall-Thompson CB, CMG (5 May 1874 – 6 July 1950) was a Royal Navy officer who played a key role in the development of the New Zealand Naval Forces and also served in the First World War as commander of HMS Philomel.

[1] Hall Thompson served in a series of overseas postings,[1] including a period in Australia as Inspector of War-like Stores at Garden Island,[2] but by 1905 was based in London.

This was in response to the desire of the New Zealand Minister of Defence at the time, James Allen, who wanted to establish a local naval force which would co-operate with the fledgling Royal Australian Navy.

[3] An approach was made to the British Admiralty for assistance and Hall-Thompson, who had hyphenated his name after his marriage to Helen Sidney Deacon in 1899, was accordingly appointed naval advisor to New Zealand.

He took Philomel on its first cruise in New Zealand service at the end of the following month but was almost immediately recalled to Wellington when it became apparent that war was to break out in Europe.

[1] After Philomel was hastily refitted for war service, Hall-Thompson took her into the South Pacific as an escort to the Samoan Expeditionary Force that captured German Samoa in September 1914.