Britain buried the Unknown Warrior on Nov. 11, 1920, in Westminster Abbey after a procession and ceremony that included stopping at the newly dedicated Cenotaph in Whitehall, London, for a playing of the Last Post.
The burial service was followed by the Great Silence, when the entire Empire and its allies during the First World War (except the U.S.) fell silent for two minutes. The Great Silence included traffic, trains and everything else that makes noise. It is still observed in Britain at 11 a.m. on the 11th of November, the eleventh hour of the eleventh day of the eleventh month, in remembrance of the Armistice that ended World War I.
These events figure in my novel.
More about the Great Silence:
Photo of the ceremony at the Cenotaph from the collection of Marion Doss.