Samuel Wallace MacDowell III (Olinda, May 26, 1846 – Paris, August 16, 1908) was a Brazilian military man, magistrate, politician, journalist and a leading voice in the abolitionist movement of Brazil.
He was orphaned by his father and mother, one year and eight months old along with his sister, and taken to Pará to be raised by his grandmother Marie Checks,[2][3] who was originally from Martinique.
In 1860 he was assigned to the Third Artillery Battalion, however due to health problems, he could not continue his career and joined the Faculty of Law of Recife, while teaching in local colleges.
MacDowell also provided basic reforms in Brazil's correctional and detention facilities, in addition to having defended Bishop Antônio de Macedo Costa during the Religious Question in the 1870s.
MacDowell established himself in Paris where he lived a frugal lifestyle, giving classes to provide for his family's livelihood.