Union Army Lt. Col. James J. Smith and officers of the 69th New York Infantry, known as the Irish Brigade, pose for a photo during the Civil War. Report of Brigadier General Thomas F. Meagher, U.S. Army, commanding Second Brigade, of the battle of Antietam. HDQRS. (IRISH BRIG.) 2nd BRIG., SUMNER’S CORPS, HANCOCK’S DIVISION, ARMY OF THE POTOMAC, In Camp on Bolivar Heights, Va., September 30, 1862 CAPTAIN: I have the honor to submit the following statement of the part which the brigade under my command performed in the battle of the Antietam: Being encamped 1 mile outside Frederick City, on this side, on the morning of the 14th of September the brigade received orders immediately to proceed to the support of General Hooker, who was at the time hotly engaged in the passes of the South Mountain with the enemy. Being halted for an hour or so, owing to the favorable reports from the headquarters of General Hooker, the brigade had an hour or so to take rest and refreshment, the first opportunity they had of doing so after a rapid and exhausting march over the rocky hills and through the tangled woods from their encampment outside Frederick City.