Photograph of the F.B. Severs Cash Store, Okmulgee, I.T. Photo was taken by John K. Hillers on May 9, 1875. Frederick Ballard Severs was a prominent rancher and entrepreneur in Indian Territory. He was the first postmasters in Okmulgee. He helped develop Okmulgee and Muskogee by constructing many of the business buildings, and he built and assisted in organizing the First National Bank of Muskogee.