Carringer observed that '' Citizen Kane '' is one of the few Welles projects based on an original story idea rather than an adaption of existing work . " Mankiewicz was hired to furnish him with what any good first writer ought to be able to provide in such a case : a solid , durable story structure on which to build , " Carringer wrote . Welles then " adapted it with the same freedom and disregard for authority with which he adapt ed a Shakespeare play or a thriller by Nicholas Blake . " The screenplay for '' Citizen Kane '' received the Academy Award for Best Writing ( Original Screenplay ) , shared by Herman J. Mankiewicz and Orson Welles
Academy Award
14th Academy Awards
Screenplay for Citizen Kane