The Post Office opened March 1, 1907, and closed on November 16, 1956.
Clarkville was named after its first postmaster, Lewis G. Clark. The post office was apparently located in Clark's farm dwelling. In 1909, Clark resigned and a new postmaster, L. M. Greenstreet, took over. The post office was moved to the location of the Greenstreet dwelling, about 6 miles to the east, and it too was likely a farm. The post office stayed with the Greenstreet family until its first closure in 1927.
The town was renamed Abilene on August 1, 1911.