Overview
The 145th Pennsylvania Infantry (Three Years’ Service) was an infantry regiment organized in Pennsylvania during the American Civil War. Composed primarily of men from Erie, Warren, Crawford, and Mercer counties, the regiment was mustered into United States service for a three-year term in late August and early September 1862. It served in the Union Army, primarily within the Army of the Potomac, and participated in many of the major campaigns and battles in the Eastern Theater.
The regiment was known for its rapid transition from civilian life to active field service, its heavy losses in several key engagements, and its continued service through the end of the war. The 145th Pennsylvania Infantry mustered out in May 1865 after participating in the Grand Review in Washington, D.C.
Organization & Service
The 145th Pennsylvania Infantry was organized at a camp near Erie, Pennsylvania, on the former grounds of the 83rd and 111th Pennsylvania regiments. The regiment was mustered into service for three years in late August and early September 1862. Colonel Hiram L. Brown, with prior militia and volunteer experience, was appointed commander, with Lieutenant Colonel David B. McCreary and other experienced officers in key positions.
Due to urgent needs at the front, the regiment was quickly sent to Chambersburg on September 11, 1862, where it was equipped with outdated arms. After a brief stay at Camp McClure, the unit advanced toward Hagerstown and arrived near the Antietam battlefield on September 17, 1862. The regiment performed picket duty and assisted in burial and care of the wounded following the battle. The sudden shift to active duty resulted in significant illness and disability among the men.
The regiment moved to Harper’s Ferry, where it was temporarily attached to the Irish Brigade, and then assigned to the 1st Brigade, 1st Division, 2nd Corps, Army of the Potomac. In October, it marched to Warrenton and then to Falmouth, Virginia. The 145th participated in the assault on Marye’s Heights at Fredericksburg in December 1862, suffering severe casualties. At Chancellorsville in May 1863, the regiment lost over 100 men captured on the skirmish line, in addition to other casualties.
The regiment arrived at Gettysburg with the 2nd Corps on July 2, 1863, and was heavily engaged, particularly at the Peach Orchard. Following Gettysburg, the 145th took part in the pursuit of Lee’s army, operations in the Shenandoah Valley, and the Mine Run Campaign. It wintered near Germanna Ford, where its camp was noted for its sanitary condition.
In the spring of 1864, the regiment received new recruits and joined the Overland Campaign, seeing action at the Wilderness, Po River, North Anna, Totopotomoy, and Cold Harbor. The regiment suffered significant losses at Cold Harbor and during the assault on Petersburg on June 16, 1864, where many were killed, wounded, or captured, including Lieutenant Colonel McCreary. The diminished regiment continued to serve in the trenches and participated in actions at Deep Bottom, Reams’ Station, and Five Forks.
After Lee’s surrender, the 145th Pennsylvania Infantry returned to Alexandria, participated in the Grand Review in Washington, and was mustered out near Alexandria on May 31, 1865. The regiment returned to Erie, Pennsylvania, where it was paid and discharged on June 5, 1865.
Research This Regiment Further
If you’d like to explore this unit’s history in more depth, regimental histories and Civil War reference works offer valuable detail.
Engagements & Campaigns
- Antietam (picket duty and aftermath)
- Fredericksburg
- Chancellorsville
- Gettysburg
- Auburn
- Bristoe Station
- Raccoon Ford
- Mine Run Campaign
- Wilderness
- Po River
- North Anna River
- Totopotomoy
- Cold Harbor
- Petersburg (June 16, 1864, and subsequent operations)
- Deep Bottom
- Reams’ Station
- Five Forks
Casualties
- Fredericksburg: 226 killed or wounded out of fewer than 500 engaged; 9 commissioned officers killed; Colonel Brown severely wounded.
- Chancellorsville: 122 killed, wounded, or captured (including over 100 captured on the skirmish line).
- Gettysburg: 90 killed, wounded, or missing out of 200 engaged.
- Petersburg (June 16, 1864): About 50 killed or wounded, 9 officers and approximately 80 enlisted men captured out of 200 engaged.
Some details are incomplete in surviving primary sources.
Field Officers & Commanders
- Colonel Hiram L. Brown
- Colonel David B. McCreary
- Lieutenant Colonel David B. McCreary
- Lieutenant Colonel Charles M. Lynch
- Major John W. Patton
- Major John W. Reynolds
- Major Charles M. Lynch
- Major James H. Hamlin
Regimental Roster
The full roster of the 145th Pennsylvania Infantry (Three Years’ Service), including officers and enlisted men, is available for genealogical and historical research. The roster provides names, ranks, and additional service details when available.
To view the complete roster, visit the 145th Pennsylvania Infantry (Three Years’ Service) Roster page.
Sources & References
- Official Records of the Union and Confederate Armies, Series I, Volumes XIX, XXV, XXVII, XXXVI, XL, XLVI
- Pennsylvania Adjutant General’s Report
- Dyer, Frederick H. “A Compendium of the War of the Rebellion”
- Fox, William F. “Regimental Losses in the American Civil War”
- The Union Army, Vol. 1 (Federal Publishing Company, 1908)