Most Serene Republic

Most Serene Republic (Serenissima Respublica in Latin) 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); consequently "Most Serene Republic" emphasizes the sovereignty of the republic.

San Marino is the only modern independent state to use the style. Although officially named simply the "Republic of San Marino", short form "San Marino", it is unofficially still referred to as the Most Serene Republic of San Marino (Italian: Serenissima Repubblica di San Marino).

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