100th Regiment, Pennsylvania Infantry

Historical Sketch:
Cols., Daniel Leasure, N. J. Maxwell ; Lieut.-Cols., James Armstrong, David A. Leckey, Matthew M. Dawson, Joseph H. Pentecost, N. J. Maxwell, Charles Wilson; Majs., David A. Leckey, Matthew M. Dawson, James Armstrong, James H. Cline, T. J. Hamilton, David Critchlow, N. J. Maxwell, James W. Bard. The 100th, known as the Round Head regiment, was recruited in the southwestern part of the state in Aug., 1861, and ordered to Washington on Sept. 2, where its organization was completed and it was mustered into the U. S. service for a three years' term. Twelve companies were recruited but one was transferred to the 105th infantry. It was next ordered to Fortress Monroe, where it embarked on what proved to be an expedition to Port Royal. Here the fleet arrived Nov. 7 and captured Forts Walker and Beauregard. Beaufort was next occupied and the regiment remained in this vicinity for several months, the men suffering very much from sickness. The 100th participated in the operations against Charleston in June, 1862, and lost very heavily in the engagement of June 16 near Secessionville. Returning to Hilton Head and Beaufort in July, it was ordered to Virginia, later being sent to Fredericksburg and attached to the 9th corps of the Army of Northern Virginia. After various marches during the month of August, the regiment met the enemy on the Bull Run battlefield, where it saw hard service. After engaging all day and losing heavily, a final charge was ordered, from which only 198 out of 450 returned unhurt. It was active at Chantilly and South mountain, but was held in reserve at Antietam, owing to its crippled condition. It was engaged at Fredericksburg and after the battle performed important duty in covering the withdrawal of the troops, being selected as "The most reliable skirmish regiment in the brigade." In March, 1863, it was transferred to the Department of the Ohio and sent to Lexington, Ky., from which place it was ordered in June to the support of Gen. Grant at Vicksburg. It participated in the fighting at Jackson, Miss., after the fall of Vicksburg, and lost many men from sickness as well as from the enemy's fire. On its return north it was ordered to East Tennessee though many of the men were not fit for active service. It participated in an engagement at Blue Springs and in the hardships of the siege of Knoxville, in spite of which almost the entire regiment reenlisted on Jan. 1, 1864. At Annapolis, the rendezvous of the 9th corps, the 100th reported in March and became a part of the 2nd brigade, 1st division, attached to the Army of the Potomac. The 9th corps was closely engaged at the Wilderness, Spottsylvania, the North Anna river and Cold Harbor. Moving to Petersburg, the 100th was repeatedly in action, notably at the explosion of the mine, the raid on the Weldon railroad, Poplar Spring Church, the Hatcher's run movements, and in the final assault on Petersburg, April 2, 1865. The regiment was mustered out at Washington on July 24, 1865. Roster:
The Roster of this unit contains the names of 3170 men.
Source:
The Union Army by Federal Publishing Company, 1908 - Volume 1
Bibliography:

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