 By 1861, the divergent sympathies of a border state had divided the members of the regiment.While most of them supported the Southern cause, and succeeded in making their way out of Baltimore when it passed under Union military control in April 1861, others served in the Union Army.In June, 1861, the Southern sympathizers organized the First Maryland Infantry, CSA, at Harpers Ferry and became part of Thomas "Stonewall" Jackson's Corps which fought the first Battle of Manassas.