Having last hosted professional baseball and the Hannibal Stags in 1955, the city debated whether Clemens Field was worth preserving.

Soon afterwards, a group led by Roland Hemond (advisor to Arizona Diamondbacks president Derrick Hall) stepped forward with a plan to renovate Clemens Field and make it home to a 2009 team in the Central Illinois Collegiate League (CICL).

Almost two months later, on August 1, 2008, the Cavemen announced their name, which was a homage to the numerous caves in Hannibal which are popular with tourists.

On November 11, 2008, the CICL announced it was merging into the new Prospect League, which the Cavemen joined as a member of the West Division, beginning in the 2009 season.

On January 6, 2017, the Prospect League announced that the Hannibal franchise had elected to suspend operations for the 2017 season.