The Purnell Legion Maryland Infantry lost 1 officer and 42 enlisted men killed or mortally wounded and 1 officer and 73 enlisted men to disease during the Civil War. It is honored by a monument at Antietam.

October 31 to December 31 Organized at Pikesville, Md., near Baltimore, under special authority of the Secretary of War and attached to Dix’s Division, Baltimore, Md
November 14-22 Expedition through Accomac and Northampton Counties, Va.
March Duty at Baltimore and with Lockwood on Eastern Shore, Va. assigned to Lockwood’s Brigade, Middle Department
May 25 Ordered to Harper’s Ferry and attached to 2nd Brigade, Sigel’s Division, Department of the Shenandoah
May 28-30 Defense of Harper’s Ferry
June Operations in Shenandoah Valley, Va., assigned to 2nd Brigade, 2nd Division, 2nd Army Corps, Pope’s Army of Virginia
August 9 Battle of Cedar Mountain
August 16-September 2 Pope’s Campaign in Northern Virginia assigned to 3rd Brigade, 2nd Division, 2nd Corps, Army of Virginia
August 21-23 Fords of the Rappahannock
August 22 Catlett’s Station
August 27-29 Plains of Manassas (Reserve)
August 30 Second Battle of Bull Run (Reserve)
September 6-22 Maryland Campaign. Assigned to 3rd Brigade, 2nd Division, 12th Army Corps, Army of the Potomac.
September 14 Battle of South Mountain (Reserve)
September 16-17
Battle of Antietam

From the monument to the west of the Dunker Church:

Occupied a line running north from this marker. Loss, 3 killed, 23 wounded.

September 22 Moved to Bolivar Heights
October Assigned to 2nd Brigade, 2nd Division, 12th Army Corps
November 9 Reconnaissance to Rippen, Va.
December Detached and assigned to duty at Frederick, Md., and in the Middle Department
February Assigned to 3rd Separate Brigade, 8th Army Corps
June Assigned to 1st Separate Brigade, 8th Army Corps
May 26 Joined Army of the Potomac in the field, assigned to 3rd Brigade, 2nd Division, 5th Army Corps
May 30-June 15 Rapidan Campaign
May 30 Shady Grove
June 1-12
Cold Harbor
June 1-3 Bethesda Church
June 16-18 First Assault on  Petersburg; Siege of Petersburg begins. Attached to 2nd Brigade, 2nd Division, 5th Army Corps
June 21-23 Jerusalem Plank Road
July 30 Mine Explosion, Petersburg
August 18-21 Weldon Railroad
September 29-October 2 Poplar Springs Church
October 2-5 Yellow House
October 7-8. Peeble’s Farm
October 24 Mustered out. Veterans and Recruits transferred to 1st Maryland Infantry.