The Battle of Vienna, Virginia was a minor engagement between Union and Confederate forces on June 17, 1861, during the early days of the American Civil War.

The Union was trying to protect the areas of Virginia opposite Washington, D.C., and established a camp at Vienna, at the end of a 15-mile (24.1 km) railroad to Alexandria.

Gen. Robert C. Schenck was transporting the 1st Ohio Infantry to Vienna by train, they were overheard by Confederate scouts led by Colonel Maxcy Gregg, who set up an ambush.

They hit the train with two cannon shots, inflicting casualties of eight killed and four wounded, before the Union men escaped into the woods.

[2] The patrol brought back to the Union Army commanders an exaggerated estimate of Confederate strength at Fairfax Court House.

Gen. Schenck with the 1st Ohio Infantry under the immediate command of Col. Alexander McDowell McCook[9] to expand the Union position in Fairfax County.

Gregg moved his artillery pieces to a curve in the railroad line between the present locations of Park and Tapawingo Streets in Vienna and placed his men around the guns.

[5][14][15] Seeing this disposition, an elderly local Union sympathizer ran down the tracks to warn the approaching train of the hidden Confederate force.

The Union force suffered several casualties but were spared from incurring even more by the slightly high initial cannon shots and by quickly jumping from the slow–moving train and either running into nearby woods or moving into protected positions near the cars.

[16] Many of the Union infantrymen took shelter behind the cars and tried to return fire against the Confederate force amid a confusion of conflicting orders.

[18] As darkness fell, the Union force was able to retreat and to elude Confederate cavalry pursuers in the broken terrain.

[19][20] When the Union commanders at Arlington got word of the attack, they sent wagons to bring back the wounded and the dead but these did not reach the location of the fighting.