Nicholas was born in 1840 in Maryland; he was 21 in 1861, the beginning of the Civil War. In the early days of the war, each state was in charge of recruiting companies of local soldiers that were then sent to fight with the Federal forces. Young Nicholas Carroll enlisted with the Patapsco Guards, a company of about 100 men out of Ellicott Mills, Howard County, Maryland in September 1861. This unit primarily served provost marshal duty -- military police -- during the first year of the war right there in Howard County. They were eventually assigned to Harper's Ferry, then to Shippensburg, Pennsylvania, then the Chambersburg-Carlisle-York-Harrisburg area, guarding various bridges and towns under the threat of Robert E. Lee's northern advance. The company was in charge of guarding various fords at the Susquehanna River during the Battle of Gettysburg on July 1, 2 and 3, 1863, but they were sent back to York and then Gettysburg itself soon after for guard duty at hospitals and prisons. Nicholas was officially mustered out of service in 1864, the same year that he and Elizabeth were married. Their son, John E. Carroll, was born February 18, 1865, in Maryland. Two daughters were born after the family moved to Pennsylvania, Steller A. in 1868, and Ada S. in 1872.
This is a card from the military pension index showing Nicholas Carroll filed for a pension in 1890. It also notes the date of his death on February 14, 1926, at age 86. He is buried in Watsontown, Pennsylvania.
It is frustrating that we can't find any photos of Nicholas Carroll, especially since he was still living in 1926. We'll keep digging. --cds/ck