The Historical Archive of the Treasure of St. Januarius is one of the few archives which has survived the Second World War, the destructions, the earthquakes. In the archive of the Deputation we can find the documents concerning the commissioning of works from illustrious artists such as Domenico Zampieri and Giovanni Lanfranco, or sculptors and silversmiths such as Lorenzo Vaccaro, Giandomenico Vinaccia and Filippo del Giudice. We can also find the music scores dedicated to the saint, the registers where his miracles have been noted down over the centuries, and extensive testimonies about the patrician families belonging to the old seggi or districts of Naples.