James R. Brockus was a native Tennessean and retired professional soldier who also played a critical role in the Battle of Blair Mountain. Born August 8, 1875 in Erwin, Tennessee, Brockus came to West Virginia following World War I, when the newly-created West Virginia State Police (WVSP) force was being organized. Invited to apply by Capt. Thomas W. Norton, the third man named as a state police company commander, Brockus enlisted on August 10, 1920. His leadership and combat experience immediately won him appointment as a lieutenant. Shortly thereafter he was promoted to captain and given command of Company B.

Brockus quickly developed a reputation as one of the most respected and feared officers in the newly formed WVSP. During his career he served throughout the state, making notable contributions to law enforcement efforts in prohibition and illegal gambling. Brockus was also an excellent training officer, and commanded the landmark May-June 1935 recruit school at Camp Conley, Point Pleasant. Ongoing conflict with the superintendent over enforcement policy abruptly led to his forced retirement in August 1935. He lived in Huntington until his death on November 16, 1966.

Brockus acquired national recognition while commanding Company B in the Mingo County martial law district, 1920-1922. He was improperly directed to enforce the governor's proclamation of martial law, only to have the state Supreme Court overrule that directive, saying only soldiers, not policemen, could enforce such law. Company B thereafter served under acting adjutant general Thomas B. Davis.

Brockus led Company B to Logan County in August 1921, to reinforce Sheriff Don Chafin's defenders opposing the Second Miner's March. When the miners were told they would likely face federal troops if they continued, most reversed course. At this point, Brockus was ordered to serve arrest warrants on several miners for stealing WVSP troopers' horses. In the process he engaged in a firefight with miners at Sharples, provoking the "Sharples Massacre" hysteria, and causing the miners to resume their march into Logan County—an action that led directly to the Battle of Blair Mountain.