Who was the 142nd PVI?

The 142nd Pa Volunteer Infantry was brought into the service of the Union Army in the American Civil War on 25 Aug 1862. The men came from all across the state of Pennsylvania, but had a distinctly western PA feel: five of the ten companies were raised in Somerset, Fayette, and Westmoreland counties. As their first order of business, they elected officers:
Col. Robert P. Cummins, Somerset County

Lt. Col Alfred B. McAlmont, Venango County

Major John Bradley, Luzerne County

The regiment rendezvoused at Camp Curtin, outside Harrisburg, and after electing officers was sent to Washington, D.C. to help construct Ft. Massachusetts, mainly clearing land and digging rifle pits. This fort was later re-named Ft. Stevens.

The 142nd took part in over 20 engagements from Fredericksburg in 1862 to Appomattox Court House in 1865, where the war was effectively ended in the east. Among those battles, were:

Fredericksburg, VA
Chancellorsville, VA
Gettysburg, VA
Wilderness, VA
Spotsylvania, VA
North Anna, VA
Totopotomy Creek, VA
Bethesda Church, VA
Cold Harbor, VA
Siege of Petersburg, VA
Weldon Railroad, VA
Poplar Spring Church, VA
Hatcher's Run, VA
Dabney's Mill, VA
Boydton Road, VA
Five Forks, VA
Appomattox, VA

The 142nd Monument in Gettysburg, PA has the regiment's losses during its 2 1/2 year service inscribed on it:

Total enrollment: 935
Killed and died of wounds: 7 officers and 133 enlisted men
Wounded: 21 officers and 409 enlisted men
Died of disease, etc.: 81 enlisted men
Captured and missing: 2 officers and 156 enlisted men
Total loss: 809

Fox's Regimental Losses states that the 142nd suffered the 9th highest casualty rate of any unit in the Union Army