The slave ship S Antônio Protetor departed on a transatlantic slave-trading voyage that would carry enslaved Africans to Brazil.

Vessel: S Antônio Protetor; flag: Portugal / Brazil; rig: Bergantim; estimated standardized tonnage: 174. People recorded in connection with the voyage: Investor: Regadas, Antônio de Queirós Monteiro; Captain: Regadas, Luís de Queiróz Monteiro; Investor: Regadas, Luís de Queiróz Monteiro. The voyage began at Pernambuco, place unspecified on 29 March 1821. Principal recorded place where captives were acquired: Luanda (West Central Africa and St Helena). Principal recorded disembarkation place: Pernambuco, place unspecified. Recorded outcome: Voyage completed as intended.