In 1894, Thomas Caspar Gilchrist from the University of Maryland first identified blastomycosis. Gilchrist initially believed the disease was caused by a protozoan, but in collaboration with W.R. Stokes, he subsequently isolated the organism, which he named Blastomyces dermatitidis.

The infection became known as Chicago disease because most early cases were identified in the Chicago area, but it was subsequently shown to be endemic to much of eastern North America. Sporadic cases have also been reported in Africa, the Middle East, and India.

Blastomycosis is a rare fungal disease often initially misdiagnosed, which can contribute to severe pulmonary illness.