This is a Portugese surname of medieval origins, and one which is also recorded in Spain. Recorded as Do Rosario and Rosario, the usual origin quoted in most dictionaries is that the surname was a nickname for a person who was born on the festival known as 'Our lady of the Rosary,' and celebrated on October 1st each year. The derivation is from the Roman (Latin) word rosarium, which literally translates as 'rose garden'. This is apparently an abstract meaning which is much associated with the cult of the Virgin Mary from about the 12th century. At that time the rose became part of the holy aura, which surrounded anything to do with the believed mother of Christ. However it remains possible at least for some nameholders, that originally the surname would have been occupational or perhaps topographical, and to have described a person who worked or lived at a 'rosarium'. An early example of the surname recording is that of Maria Do Rosario who married Mathias Vieira at Santa Beatri, Agua de Pena, Funchal, on March 7th 1707.