Man in uniform showing Airplaine to the other uniformed man

Captain Sempill showing a Gloster Sparrowhawk to Admiral Tōgō Heihachiro (1921), via WikiCommons.

Lord Sempill and Japan: Traitor or Spy-Myth?

The 19th Lord Sempill (1893-1965) was a distinguished aviator and a lifelong friend of Japan.  He led an unofficial British air mission to the Imperial Japanese Navy in the early 1920s, and subsequently fell under suspicion of disclosing classified information over the years 1923-1926 and 1939-1941. MI5’s extended investigations were inconclusive. But with the release of agency materials from the late 1990s onwards, Sempill attracted interest from historians and media alike. In 2012 he was labelled “the traitor of Pearl Harbor.”

In this lecture, Alex Hardie will argue that the archival evidence, together with fresh assessment of Sempill’s actions in their professional and political contexts, does not support the prevailing view of Sempill as a spy who betrayed British and American interests. The Japan Society, of which Sempill was an active member, features in both phases of the story, in his 1925 lecture on the air mission, and in the climacteric Council meeting of 10 December 1941.

Dr Alex Hardie is an Honorary Fellow in the School of History, Classics and Archaeology in the University of Edinburgh.  For 35 years (1973-2001; 2005-2012) he was a member of the British Foreign Service, with extensive responsibilities in the field of national security.

If you have any questions, please call the Japan Society office on 020 3075 1996 or email events@japansociety.org.uk.


Booking Info
  • Please note this is an in-person event subject to Covid regulations and the health and safety requirements at the venue. More details will be provided to attendees closer to the date.

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