We don't know what Puzo intended when he chose his characters for the novel. But he was describing the real-life "Castellemmarese War" of 1930-31. It is a fact that the man he pictured as Vito's foe, "Salvatore Maranzano," was, in real life, Joe (the Boss) Masseria. Masseria operated in Manhattan, and tried to make an alliance with Capone. The real-life Salvatore Maranzano operated in Brooklyn. What's more, in real life, Maranzano had Masseria killed in a Brooklyn restaurant--just as Puzo described Vito leaving "Maranzano" dead in a Brooklyn restaurant.

You might be interested to know how, in real life, Maranzano outsmarted Masseria: Charlie (Lucky) Luciano was one of Masseria's top men. Maranzano flattered, cajoled, and eventually tortured Luciano into betraying his boss, Masseria. Luciano invited Masseria to have lunch and play cards in a Brooklyn restaurant. Then Luciano excused himself to go to the men's room. While he was there, three shooters entered the restaurant and riddled Masseria with bullets, leaving him dead with the ace of spades in his hand. The shooters were recruited by Luciano's boyhood friend, Meyer Lansky. The shooters were Benjamin (Bugsy) Siegel, Lansky's partner; Abraham (Bo) Weinberg, Dutch Shultz's top gun; and Guiuseppe (Joe Adonis) Doto.