Maj. Gen. Philip H. Sheridan's campaign in the Shenandoah Valley against Lt. Gen. Jubal A. Early's Confederates had achieved decisive results by October 1864. Twice, at Winchester on september 19th and Fisher's Hill on September 22nd, the Union army had defeated the Confederates. By early October, the Federals had occupied the upper valley near Harrisonburg, destroying crops, farms, and mills. Sheridan's successful campaign was hampered only by the operations in his rear waged by the confederacy's incomparable guerrilla officer Lt. Col. John S. Mosby.
Mosby had forged the 43rd Virginia Battalion, since its formation on January 1863, into an indestructable body of partisan rangers. Operating from the region east of the blue ridge Mountains known as "Mosby's Confederacy", the rangers descended on Union wagon trains, outposts, and railroad trains and crews. Superb horsemen, they defiled all atempts at eradication. Sheridan wrestled with solutions, even creating an elite body of scouts with the sole mission of destroying the ubiquitous rangers. But time and again Mosby struck, inflicting casualties, destroying or capturing supplies, and frustrating Union commanders.
On the night of the 12th, Mosby, with 84 rangers, reentered the valley on another raid. All day on the 13th, the raiders hid north of Winchester. With nightfall, they remounted and rode northward, halting about 10:00 P.M. at a deep cut near Brown's Crossing on the baltimore & ohio railroad, several miles west of Harpers ferry. A detachment hurriedly displaced a few rails in the cut, then patiently waited.
Between 2:00 and 3:00 A.M., the westbound passenger express came rattling out of the darkness.
When the engines hit the gap in the rails, it lurched suddenly into the bank in a loud crash. Inside the cars, passengers tumbled from their seats. Within minutes, the the rangers swarmed through the damaged cars. A Union soldier resisted and was shot instantly. The rangers herded the passengers outside, and Mosby ordered the cars and engine burned. Two rangers held a satchel and a tin box they had taken from 2 army paymasters. Inside was $173,000 in Greenbacks, which would be divided into 84 shares. While the train burned, the rangers rode away into the West Virginia blackness. Mosby's "Greenback raid" brought operations on the vital railroad to a temporary standstill.