One reason may be this:
Sir Percy
Scarlet Pimpernel
I understand in the first draft he was known as the red carnation. A scarlet pimpernel is a common hedgerow flower in England. Scarlet sounds more romantic than red, pimpernel has a lovely sound, I think it was a good choice to change it!
Anagallis arvensis is the latin name for the flower.
little edit
He also puts scarlet pimpernels on his notes :D
Scarlet Pimpernel, morning glory, pinecones
The first symbol we see in the Scarlet Pimpernel is the flower the book is name after. The bloodiness and death of the revolution against the red of the flower which often stands for life.
A scarlet pimpernel is first and foremost a flower, but it's also the name, or code name if you wish, for a character in an adventure novel. The Scarlet Pimpernel rescued French aristocrats from being inprisoned and/or beheaded during the French revolution.
sir Percy blakeney
The Scarlet Pimpernel was created in 1905.
The Scarlet Pimpernel - 1999 The Scarlet Pimpernel 1-1 is rated/received certificates of: UK:12 (VHS/DVD rating)
Adventures of the Scarlet Pimpernel was created in 1929.
The Triumph of the Scarlet Pimpernel was created in 1922.
The League of the Scarlet Pimpernel has 313 pages.
The League of the Scarlet Pimpernel was created in 1919-03.
The duration of The Adventures of the Scarlet Pimpernel is 1800.0 seconds.
The duration of Return of the Scarlet Pimpernel is 1.57 hours.