The country derives its name from Saint Marinus, a stonemason from the then-Roman island of Rab in present-day Croatia. Born in AD 275, Marinus participated in the rebuilding of Rimini's city walls after their destruction by Liburnian pirates. Marinus then went on to found an independently ruled monastic community on Mount Titan in AD 301; thus, San Marino lays claim to being the oldest extant sovereign state, as well as the oldest constitutional republic.