[2] It was established at statehood on November 16, 1907, and named for Douglas H. Johnston, a governor of the Chickasaw Nation.

The Chickasaw Nation named the town of Tishomingo as its capital and built a brick capitol building there in 1856.

The Pleasant Grove Mission School and the Chickasaw Academy were founded by the Methodist Episcopal Church in 1844.

The Presbyterians, in partnership with the Chickasaw Nation, opened the Wapanucka Female Manual Labour School in 1852.

[3] The Chickasaw government joined the Confederate States of America after the outbreak of the Civil War.

When Confederate troops occupied the area, they used the stone building at Wapanucka as a hospital and a prison.

In 1911, the MO&G built a spur west to Bromide, an early-twentieth-century health resort, capitalizing on the vicinity's natural springs.

Now the Burlington Northern and Santa Fe, which acquired the Frisco in 1980, is the only railroad left in the county.

[4] The northern part of the county lies in the Arbuckle Mountains, which consists of rock outcroppings and rolling hills.