FTP, Dario Fo, Italo Calvino, and Luigi Pirandello all hail from what nation?
One author from this country wrote a play in which an inspector is constantly outwitted by The Maniac, whom he is trying to interrogate, Accidental Death of an Anarchist.  Another author from this nation wrote a novel detailing a conversation between Marco Polo and Kublai Khan, describing the title entities, Invisible Cities. While this country's most famous playwright wrote one play in which a character is convinced that he's Emperor Henry IV, and one in which a family barges into a rehearsal of a play to demand that the Manager help them finish their story, Six Characters in Search of an Author. FTP, Dario Fo, Italo Calvino, and Luigi Pirandello all hail from what nation?
One author from this country wrote a play in which an inspector is constantly outwitted by The Maniac, whom he is trying to interrogate, Accidental Death of an Anarchist.  
Italy