Since it contains a real historical event, the Day of the Dupes, the timing is the autumn of 1630 when Cardinal Richelieu (the 'Red Robe') was Chief Minister for Louis XIII.
The plot features one of Weyman's more interesting characters, Gil de Berault, a gambler and notorious dueller living in Paris who sometimes acts as hired muscle for the Cardinal.
He fights one duel too many and is given the choice between execution or helping the Cardinal capture a key Huguenot rebel.
Conan Doyle wrote that Under the Red Robe had "the most dramatic opening of any historical novel I know" and Siegfried Sassoon described his excitement as a schoolboy on first reading a copy.
[4] A third version was made in 1937, the British swashbuckler Under the Red Robe directed by Victor Sjöström and featuring Conrad Veidt as Gil de Berault, Raymond Massey as the Cardinal and French actress Annabella as the romantic interest.