At Trion Factory, military activity intensified in mid-September 1863 as Colonel E.M. McCook reported on September 13 that Wheeler's force, which had left for Lafayette the day before on his approach, had returned to the crossroads at the junction of the Ringgold and Lafayette roads, that he could not drive them off, and that he was moving to join the main force while leaving a squadron at the junction of the Trion Factory and Broomtown Valley roads to protect that flank. Later that day, W.M. Sinclair, assistant adjutant-general, relayed General Crook's message that troops had gone on to Lafayette, captured an infantry picket, gathered the desired information, and received scout reports of a heavy Confederate column of infantry, cavalry, and artillery moving toward Summerville on the Lafayette road, with instructions that if contact occurred McCook should fall back slowly, watch their movements, and report to General Stanley. On September 14, Confederates reoccupied Trion with a brigade of infantry, Helm's Brigade under Brigadier General Benjamin Hardin Helm, who was killed in battle five days later at Chickamauga; Helm was Mary Todd Lincoln's brother-in-law, and Abraham and Mary Lincoln mourned his death. On September 15, near the covered bridge across the Chattooga River on the Summerville-Lafayette road, the battle of Trion Factory took place, where Confederate cavalry and infantry repulsed a brigade of Federal cavalry. General Joseph Wheeler's records gave Confederate losses as 7 men and Federal losses as 55 men, and the dead were buried beside the road on the battlefield at what is now Trion Cemetery. Trion Factory, now Mount Vernon Mills, remained in operation, and within days the wider campaign culminated in the Battle of Chickamauga on September 19-20, 1863.