The real d'Artagnan's life was used as the basis for Gatien de Courtilz de Sandras' novel "Les mémoires de M. d'Artagnan". Alexandre Dumas in turn used Sandras' novel as the main source for his d'Artagnan Romances ("The Three Musketeers", "Twenty Years After" and "The Vicomte de Bragelonne"), which cover d'Artagnan's career from his humble beginnings in Gascony to his death at Maastricht. Although Dumas knew that Sandras's version was heavily fictionalised, in the preface to "The Three Musketeers" he affected to believe that the memoirs were real, in order to make his novel more believable.