Coat of arms of the Most Serene Republican Monarchy of Naples (1647)
Own work, source: Napoli, repubblica, pubblica del 1648, "The coat of arms was a red shield with the motto S.P.Q.N. (i.e., Senatus Populusque Neapolitanus), in imitation of the well-known S.P.Q.R., the initialism of the Latin phrase, Senatus Populusque Romanus ("The Senate and the People of Rome"), Thus, the Neapolitan phrase meant "The Senate and People of Naples." The coat of arms contained the crest of the duke of Guise."
Samhanin