The park is named after Hiram B. Cahill, who originally owned the land where the park and nearby Diridon Station (formerly Cahill Depot).[3] Hiram's widow, Mary Welch Cahill, eventually sold the land to Southern Pacific Railroad with the request that the station they erect be named in his memory.
The Cahill Park is one of the affected stakeholders in Google's planned revitalization of the Diridon area of Downtown San Jose.[4]