Who is Lucien Antoine Hector Savinien de Ladon, Comte de Graay from Flying Colours and what is their importance?

Count Lucien is a widowed, elderly man, who in addition to his wife, lost all three of his sons in the Napoleonic Wars. He makes his home in a small castle, in which he provides Hornblower, Bush, and Brown protection and shelter when they are fugitives.