Built in 1938, Clemens Field had fallen into disrepair in recent years. Having last hosted professional baseball 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.
On June 10, ground was broken for Clemens Field's renovation. Almost two months later, on August 1, the Cavemen announced their name, which is an homage to the numerous caves in Hannibal which are popular with tourists.
On November 11, the CICL announced it was merging into the new Prospect League, which the Cavemen will be joining as a member of the West Division.