J. Wilmer Hershey was born in 1894 in Lancaster, PA. He attained a degree in architecture from the prestigious Carnegie Institute of Technology (now Carnegie Mellon University).

In 1924, Hershey became a draftsman in offices of the renowned Pasadena, CA office of E. Wallace Neff. In 1925, Hershey became a senior draftsman and Consultant in Design in the Community Drafting Room of the Architectural Advisory Committee of Santa Barbara. Here he worked extensively with architect George Washington Smith, the master of the Spanish Colonial style, on the rebuilding of Santa Barbara after the earthquake.

Hershey is known for his romantic sketches and renderings including the redesigning elevations for the Santa Barbara Courthouse in a single night. Hershey buildings are elegant in massing, scale and proportion with meticulous attention to details such as fine wrought iron and hewn beams. He was widely published in California Southland and Architectural Digest.

In 1925, Hershey also established his own Pasadena-based practice. He soon expanded to become Hershey, Seares, and Hill when he was commissioned by developer Ole Hanson to design the planned community of San Clemente.

Hershey was struck down by bacterial endocarditis in the prime of his career and was unable to finish the commission. He died on August 29, 1926 at the age of 32, leaving a wife, Sarah Elizabeth Brown, and two young sons, J. Wilmer Jr. (Jake), age 6 and R. Ivan Hershey, age 2.