People who came from Portugal brought nobility titles with them. After independence from Portugal, Brazilian monarchy also awarded titles to persons in Brazil. The kings rewarded persons who performed a heroic deed, attained a notable achievement, or held a prominent position in government by granting them a noble title. The nobility was a significant feature of Brazilian society throughout the 19th century.
If your research in the original records of Brazil indicates that your ancestor was of the noble class, there are additional records that will be helpful in your research. Grants of nobility and nobility legitimizations are kept in public archives of Brazil.
Although some original records such as the grant of nobility still exist, you can usually adequately accomplish most nobility research in secondary sources. These include published or manuscript genealogies of noble families. The noble class has been anxious to preserve its identity. This has lead to the publication of many noble lines of Brazil. Numerous publications are available to help you trace a noble family. Some of those available through the Family History Library include:
Cunha, Rui Vieira da. Estudo da nobreza brasileira (Study of Brazilian Nobility). 2 vols. Rio de Janeiro: s.n., 1966–. (FHL book 981 D55e; film 0962230 item 5 and 0928502 item 3)
Le Royaume de Portugal - l’empire du Brésil (The Royals of Portugal - the Imperials of Brazil). 2 vols. Paris: CEDRE, 1986–1987. (FHL book 940 D5pb)
Sanches de Baena e Farinha, Augusto Romano. Diccionário aristocrático, que contém todos os alvarás de foros da casa real, médicos, reposteiros e porteiros da real câmara, títulos e cartas do conselho fiel extracto dos livros do registro das mercês existentes no Archivo Público do Rio de Janeiro, desde 1808 até septembro de 1822 (Dictionary of the Royal House, Doctors, Chamberlains, and Doormen of the Royal Chamber, Titles and Letters of the Council: Faithful Extract of Record Books of the Titles Found in the Public Archive of Rio de Janeiro, from 1808 to September 1822). Lisboa: Panorama, 1867. (FHL book 946.9 D5s; films 0496779 item 3 or 0599686 item 2)
Nobility studies have been done for the states of Pernambuco and São Paulo:
Fonseca, Antônio José Victoriano Borges da. Nobiliarchia pernambucana (Peerage book for [the state of] Pernambuco). 2 vols. Rio de Janeiro: Bibliotheca Nacional, 1935. (FHL book 981.34 D2f; film 1162429 items 3–4)
Leme, Pedro Taques de Almeida Paes. Nobiliarchia paulista: histórica e genealógica (Peerage book for [the state of] São Paulo: historical and genealogical). Rio de Janeiro: Imprensa Nacional, 1926. (FHL film 1102979 item 2)
BRAZIL, [COUNTY]- NOBILITY