100th Pennsylvania Infantry

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

100th Pennsylvania Volunteer Infantry
Active August 31, 1861 to July 24, 1865
Country United States
Allegiance Union
Branch Infantry
Engagements Battle of Secessionville
Second Battle of Bull Run
Battle of Chantilly
Battle of South Mountain
Battle of Antietam
Battle of Fredericksburg
Siege of Vicksburg
Siege of Jackson
Knoxville Campaign
Rapidan Campaign
Battle of the Wilderness
Battle of Spotsylvania Court House
Battle of North Anna
Battle of Totopotomoy Creek
Battle of Cold Harbor
Siege of Petersburg
Battle of the Crater
Battle of Globe Tavern
Battle of Boydton Plank Road
Battle of Fort Stedman
Appomattox Campaign
Third Battle of Petersburg

The 100th Pennsylvania Volunteer Infantry ("The Roundheads" and "The Round Head Regiment") was an infantry regiment that served in the Union Army during the American Civil War.


The 100th Pennsylvania Infantry was organized at Pittsburgh, Pennsylvania and mustered in August 31, 1861 for a three-year enlistment under the command of Colonel Daniel Leasure.

The regiment was attached to Stevens' 2nd Brigade, Sherman's South Carolina Expedition, to April 1862. 2nd Brigade, 2nd Division, Department of the South, to July 1862. 2nd Brigade, 1st Division, IX Corps, Army of the Potomac, to September 1863. 3rd Brigade, 1st Division, IX Corps, to April 1863. 3rd Brigade, 1st Division, IX Corps, Department of the Ohio, to June 1863. Army of the Tennessee, to August 1863, and Army of the Ohio, to March 1864. 2nd Brigade, 1st Division, IX Corps, Army of the Potomac, to June 1864. 1st Brigade, 1st Division, IX Corps, to September 1864. 3rd Brigade, 1st Division, IX Corps, to July 1865.

The 100th Pennsylvania Infantry mustered out July 24, 1865.

Detailed service[edit]

Left Pennsylvania for Washington, D.C., September 2, and duty there until October 9. Moved to Annapolis, Md., October 9. Sherman's Expedition to Port Royal Harbor, S.C., October 21-November 7, 1861. Capture of Forts Walker and Beauregard, Port Royal Harbor, November 7. Occupation of Beaufort, S.C., December 8, and duty there until June 1862. Port Royal Ferry, Coosa River, January 1. Operations on James Island, S.C., June 1-28. Legaire's Point, James Island, June 3. Skirmishes on James Island June 3-4. Battle of Secessionville, James Island, June 16. Evacuation of James Island and movement to Hilton Head, S.C., June 28-July 7. Moved to Newport News, Va., July 12-17, then to Fredericksburg August 4-6. Operations in support of Pope August 6-16. Pope's Campaign in northern Virginia August 16-September 2. Battle of Groveton August 29. Second Battle of Bull Run August 30. Battle of Chantilly September 1. Maryland Campaign September 6-24. Battle of South Mountain September 14. Battle of Antietam September 16-17. Marched up the Potomac River to Leesburg, then to Falmouth October 11-November 18. Battle of Fredericksburg December 12-15. Burnside's 2nd Campaign, "Mud March," January 20-24, 1863. Moved to Newport News, Va., February 13, then to Covington, Ky., March 20-28. Duty in District of Kentucky. At Paris, Nicholasville, Lancaster, Stanford, and Somerset until June. Movement through Kentucky to Cairo, Ill., June 4-10, then to Vicksburg, Miss., June 14-17. Siege of Vicksburg June 17-July 4. Advance on Jackson, Miss., July 5-10. Siege of Jackson July 10-17. Duty at Milldale until August 6. Moved to Covington, Ky., then to Crab Orchard, Ky., August 6-18. Marched to Knoxville, Tenn., September 10-26, and duty there until October 3. Action at Blue Springs October 10. Knoxville Campaign November 4-December 23. Campbell Station November 16. Siege of Knoxville November 17-December 4. Repulse of Longstreet's assault on Fort Saunders November 29. Pursuit of Longstreet December 5-24. At Blain's Cross Roads until January 1864. Veterans marched over the Cumberland Mountains to Nicholasville, Ky., January, and on furlough until March. Ordered to Annapolis, Md., and duty there until April. Rapidan Campaign May 4-June 12. Battle of the Wilderness May 5-7. Spotsylvania May 8-12. Ny River May 10. Spotsylvania Court House May 12-21. Assault on the Salient May 12. North Anna River May 12-21. Ox Ford May 24. Line of the Pamunkey May 26-28. Totopotomoy May 28-31. Cold Harbor June 1-12. Bethesda Church June 1-3. Before Petersburg June 16-18. Siege of Petersburg June 16, 1864 to April 2, 1865. Mine Explosion, Petersburg, July 30, 1864. Weldon Railroad August 18-21. Poplar Springs Church September 29-October 2. Reconnaissance on Vaughan and Squirrel Level Road November 8. Boydton Plank Road, Hatcher's Run, October 27-28. Fort Stedman March 25, 1865. Appomattox Campaign March 28-April 9. Assault on and fall of Petersburg April 2. Occupation of Petersburg April 3. Pursuit of Lee April 3-8. Moved to Washington, D. C, April 21-28, and duty there until July. Grand Review of the Armies May 23.


The regiment lost a total of 409 men during service. Sixteen officers and 208 enlisted men were killed or mortally wounded in combat. Two officers and 183 enlisted men died from disease-related causes.


  • Colonel Daniel Leasure
  • Colonel Norman J. Maxwell
  • Lieutenant Colonel David A. Leckey - commanded at the Battle of Antietam
  • Lieutenant Colonel Joseph E. Pentecost - commanded at the Battle of the Crater (while still at the rank of captain) after Cpt. Oliver was killed in action; mortally wounded in action at the Battle of Fort Stedman
  • Major Thomas J. Hamilton - commanded at the Battle of the Crater where he was mortally wounded in action
  • Major Norman J. Maxwell - commanded at the Battle of Fort Stedman after Ltc. Pentecost was mortally wounded in action
  • Captain James E. Cornelius - commanded at the Second Battle of Bull Run after Col. Leasure was wounded in action
  • Captain Walter Oliver - commanded at the Battle of the Crater after Maj. Hamilton was mortally wounded in action; killed in action there

Notable members[edit]

See also[edit]


  • Bates, Samuel P. and Horace B. Durant. A Brief History of the One Hundredth Regiment (Roundheads,) (New Castle, PA: Jas. C. Stevenson), 1884.
  • Dyer, Frederick H. A Compendium of the War of the Rebellion (Des Moines, IA: Dyer Pub. Co.), 1908.
  • Pettit, Frederick. Infantryman Pettit: The Civil War Letters of Corporal Frederick Pettit, Late of Company C, 100th Pennsylvania Veteran Volunteer Infantry Regiment, "The Roundheads," 1862-1864 (Shippensburg, PA: White Mane Pub. Co.), 1990. ISBN 0-9425-9716-8
  • Schriber, Carolyn Poling. A Scratch With the Rebels: A Pennsylvania Roundhead and a South Carolina Cavalier (Chicora, PA: Mechling Bookbindery), 2007. ISBN 0-9793-7720-X
  • This article contains text from a text now in the public domain: Dyer, Frederick H. (1908). A Compendium of the War of the Rebellion. Des Moines, IA: Dyer Publishing Co.

External links[edit]