The Sooner State League was a Class D minor league baseball league that operated from 1947 through 1957. The league owners kept it alive in 1958, anticipating a return to play in 1959. However, when only Ardmore and Paris, Texas, were able to secure working agreements, the League folded on February 12, 1959. It was the last Class D league west of the Mississippi River. The league was based primarily in Oklahoma.