John R. Slattery (1851–1926)
Born in New York City, Slattery was ordained as a Mill Hill priest in 1877. His ministry was dedicated to African-Americans and he crusaded for equality for black Catholics within the Church. His loss of a bitter battle over the seminary training and ordination of blacks in the 1890s set in motion an increasing disillusionment with the Church, and he exited the priesthood in 1906.
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Book
See also CHn's Bibliography on Catholicism and African-Americans