We do not necessarily come to the same result if we study dramatic texts within the framework of literary institutions and contexts, or within the framework of theatrical institutions and their connections with performativity. The dramatic oeuvre of József Katona (1791–1830) has primarily been studied within the context of literary history. His early works, though, were strongly connected to theatrical practice, of which very few data have remained. One of them is the site in the city of Pest, the “Rotunda,” where several of his translations, adaptations, and original plays were performed. Another source are the showbills, which include several useful pieces of information. The essay studies how reliable these sources are and to what extent the remains of a building or programme posters can be considered documents.