On the morning of August 31, 70 miners led by John Wilburn met three guards from Chafin's army at Blair Mountain. Each side asked for a secret password then realized they were enemies and began shooting. All three guards and one miner were killed. Fighting spread along a 10-mile front. Despite its smaller numbers, Chafin's army held its position.

For three days, heavy gunfire echoed from Blair Mountain, but both sides were unorganized and ineffective.

Governor Morgan appealed to Washington for help. President Warren Harding sent 2,000 federal troops, including a chemical warfare unit and a squadron of bombers.

As federal troops reached Blair Mountain, Chafin's army disbanded. Almost immediately, miners began laying down their arms. Many said they could not bring themselves to shoot at soldiers in the U.S. Army.

The Battle of Blair Mountain was America's largest insurrection since the Civil War, yet only 12 miners and four of Chafin's men were killed.