Most Serene Republic (Latin: Serenissima Respublica; Italian: Serenissima Repubblica; Polish: Najjaśniejsza Rzeczpospolita) is a title attached to a number of European states through history.
By custom, the appellation "Most Serene" is an indicator of sovereignty (see also Serene Highness or Most Serene Highness for a sovereign prince).
When used in the past, the title "Most Serene Republic" emphasized the sovereignty of the republic.
Currently, no country officially calls itself a "Most Serene Republic": Only two modern independent nations are still sometimes referred to by this style: San Marino, officially "the Republic of San Marino" (Italian: Repubblica di San Marino).
[1] Poland, while officially "the Republic of Poland" (Polish: Rzeczpospolita Polska), is also at times called "the Most Serene Republic of Poland" (Polish: Najjaśniejsza Rzeczpospolita).