Armand Duval first appears in the younger Alexandre Dumas's 1848 novel La Dame aux Camélias (Camille or The Lady of the Camellias in English). The book has been adapted numerous times into various forms of media -- Armand in the novel is not so nice as he is in the film adaptations that I have seen. He is dramatically lovesick and jealous, and very cruel at times because of it. In the 1921 and 1936 versions at least he is more well intentioned (and a brunette).
Armand, Seigneur de Sillègue, d'Athos, et d'Autevielle, better known as Armand d'Athos, was a Gascon black musketeer of the Maison du Roi in 17th century France. (Wikipedia) Armand's name was used for the character of Olivier Athos in Alexander Dumas' 'The Three Musketeers'.
Armand Hammer (1898 – 1990) was an American industrialist and tycoon. It is a common urban legend that the brand name, Arm & Hammer, originated with or is related to him, as Hammer did own some stock in the company and served on its Board of Directors in the '80's. The truth is, Hammer only bought stock in the company as a joke!
Armand was the brother of Marguerite St. Just (the wife of Sir Percy Blakeney) in the classic novel, book, and movie "The Scarlet Pimpernel" by Baroness Orczy.
Armand was the name given to a vampire in Anne Rice's Vampire Chronicles. Before he came to Paris he was called Amadeo "he who loves God" but his name was changed due the nature of his new position, leader of a coven of vampires. Armand comes from the name Herman, which means "leader" or "military man."