The 1921 Miners' March on Logan was probably the largest armed uprising in American labor history. It involved more than 15,000 coal miners opposed by more than 5,000 mine guards, deputy sheriffs, and state police, 2,500 U.S. soldiers, and 14 bombing planes.

On August 1, Sid Hatfield, chief of police of Matewan and a hero among the miners for his role in the 1920 Battle of Matewan, was shot to death by Baldwin-Felts detectives as he approached the McDowell County courthouse in Welch. A week later, on August 7, 1921, 5,000 miners met in Charleston to present demands to Governor Morgan. Encouraged by United Mine Workers district president Frank Keeney and others, miners began to assemble later that night at Lens Creek near Charleston to prepare to march south. They intended to overthrow the governor's proclamation of martial law in Mingo County and to wipe out the anti-union mine guard and deputy sheriff systems in Logan and Mingo counties.

Union leader Bill Blizzard served as field commander. World War I veterans among the miners helped to organize the marchers along military lines. They used sentries, patrols, codes, and passwords, and had their own doctors, nurses, and medical and sanitary facilities, commissaries, and food tents.

On August 24, the march began. President Harding sent Brig. Gen. Henry Bandholtz to evaluate the situation and issued an ultimatum telling the miners to end the march. The miners continued. On August 25, they began arriving at Blair Mountain in northern Logan County. Sheriff Don Chafin, a hated symbol of anti-unionism in southern West Virginia, met them there with a combined force of deputies, mine guards, civilian volunteers, and others. Chafin's men had fortified their position on top of the ridge and were armed with machine guns and explosives. On August 28, the marching miners learned that deputies under Chafin had killed five pro-union men. This news encouraged the marchers to push on to the peak of Blair Mountain.

By September 1, the miners had captured half of the 25-mile mountain ridge and were ready to descend upon Logan. President Harding, however, placed the strike zone under martial law, and ordered federal troops and a squadron of bomber aircraft into the state. Unwilling to resist U.S. soldiers, the miners agreed to lay down their guns.

Following the Battle of Blair Mountain, Keeney, Blizzard, union leader Fred Mooney, and more than 550 marchers were indicted on charges ranging from murder to treason against the state of West Virginia. All the union officials were acquitted, mostly for lack of evidence. One marcher, Walter Allen, was found guilty of treason; he jumped bail and disappeared while the case was pending in the state Supreme Court. Another, lay preacher John Wilburn, was convicted of murder and sentenced to ten years. Governor Morgan pardoned him in 1925.