On Monday, August 8, 1864, a hot and sultry day, Capt. John McMenamin of the 15th New York Volunteer Cavalry and Capt. James Fleming of the 16th New York Volunteer Cavalry stopped at St. Mary's Church on the Ox Road in Fairfax with a command of 60 troopers, who were resting, eating supper, and feeding their horses. Shortly after 5 p.m., vedettes sounded the alarm that Confederate cavalry were approaching from the south on the Ox Road. The Union troopers mounted and formed a line of battle, with the left wing at the church's front door and the line extending across the road facing south. The Confederates were 39 Partisan Rangers of the 43rd Battalion of Virginia cavalry led by Col. John S. Mosby. After crossing the railroad tracks and rising toward the church, they formed a line 150 yards south of the Federals. Mosby rode before his men shouting, "Come on men, victory or death!" The Federals fired their carbines sporadically, causing several of their horses to bolt and disrupt their line. Seeing this, Mosby and his men charged with pistols blazing. None of Mosby's men carried carbines or sabers, only six-shot revolvers; all had two, and some had four. The Union line broke and fled in disorder, pursued as far as Fairfax Courthouse. When the fighting ended, five Union troopers were dead, including Capt. Fleming, eight were wounded, and twenty were captured, while Mosby also took 39 horses. Three of Mosby's Rangers were reported wounded. Capt. Fleming was buried in an unmarked grave at Falls Church Cemetery, and St. Mary's Church had been built in 1858 by Catholic immigrants from Ireland.
