The Mainguy Report

The Mainguy Report, October 1949. Click for enlargement.

Edmond Rollo Mainguy, OBE, CD (11 May 1901 – 29 April 1979) served as an active Royal Canadian Navy officer during the Second World War, inter alia, commanding HMCS Assiniboine, then HMCS Ottawa. Promoted captain, he took overall command of RCN destroyers in Halifax in 1941; appointed acting commodore in 1942 he took command of RCN destroyers in Newfoundland, before being appointed Chief of Naval Personnel. He then commanded HMCS Uganda in the Pacific. In 1948, he was appointed Flag Officer Atlantic Coast.

In early 1949, the RCN was shaken by three almost simultaneous cases of mass insubordination variously described as "incidents" or "mutinies": On 26 February, when the destroyer HMCS Athabaskan was on a fuelling stop at Manzanillo, Colima, Mexico, ninety Leading Seamen and below - constituting more than half the ship's company - locked themselves in their messdecks, and refused to come out until getting the captain to hear their grievances. On 15 March, in another destroyer - HMCS Crescent, at Nanjing, China - eighty-three junior ratings held a similar protest. On 20 March, thirty-two aircraft handlers on the carrier HMCS Magnificent, which was on fleet manoeuvres in the Caribbean, briefly refused an order to turn to morning cleaning stations. Defence Minister Brooke Claxton appointed Rear-Admiral Rollo Mainguy, Flag Officer Atlantic Coast, to head a commission of inquiry. The Mainguy Report concluded that no evidence was found of Communist influence or of collusion between the three crews. Far-reaching recommendations were made.

While the incidents were serious, the term 'mutiny' was avoided, and the Commission's report was necessary. In a 1949 context, it has withstood the test of time, but subsequent research has been critical in a number of areas.

For more details, see the original report, a more recent (2000) article by LCdr Richard Gimblett who later served as RCN Command Historian and K.D. Calow's 2016 PhD thesis at Wilfred Laurier University:

Mainguy Report - the official report of October 1949
What the Mainguy Report never told us - article by Dr. Richard Gimblett
The Post-war ‘Incidents’ in the Royal Canadian Navy, 1949 - by Dr. Richard Gimblett
Mainguy Report - thesis "A Sickly Season: The Royal Canadian Navy and the Mainguy Commission", K.D. Calow

See also our catalogue entry for the Mainguy report.



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