Ch1:E2: When the Foreign Office Blundered, by Hon Harold Nicolson, August 4, 1914

From a channel Lumen includes in full: The Western Front Association, a WWI history charity, posts lectures by historians and readings of first-hand veterans' accounts of the Great War.

A 13-minute video from The Western Front Association's catalogue; the title names its topic.

Video by The Western Front Association, played through YouTube's embedded player.