This article describes a historical case study of E. J. Edmunds, a Black mathematics student and teacher in 19th-century New Orleans. Edmunds's career as a student and then teacher of mathematics, which stretched from the antebellum era through Reconstruction and into segregation, was filled with obstacles and indignities but also with improbable successes. Edmunds proved to be among the world's top mathematical talents in 1871 by passing the grueling admissions exam for France's École Polytechnique. The purpose of the present article is to examine the implications that this historically rare example of Black mathematical achievement in the 19th century has for metanarratives of Black obstacles and achievement in mathematics education.