Samuel Edmund Nichols was born on February 17, 1842, in Brookfield, Massachusetts, to Proctor and Betsey Nichols. His father was a farmer who owned $2,500 of real estate in 1850. By the early 1860s, Nichols was attending school in Northampton, Massachusetts. He enlisted in the Union army on July 15, 1862, and mustered in as a private in Company G of the 37th Massachusetts Infantry on August 30. The regiment took part in the Battle of Fredericksburg, the Battle of Chancellorsville, the Battle of Gettysburg, the Battle of the Wilderness, and the Siege of Petersburg. He was promoted to 2nd lieutenant on August 30, 1864, and to 1st lieutenant on May 15, 1865. He mustered out in Washington, D.C., on June 21, 1865.
After the war, Nichols returned to his parents’ household in Brookfield, Massachusetts. He married Orpha Clark in Northampton on November 21, 1866. They had at least three children: Walter, born around 1871; Florence, born around 1873; and Edith, born around 1876. Nichols ran a music store in Pittsfield, Massachusetts, and he owned $3,000 of personal property in 1870. He moved to Buffalo, New York, sometime after 1880, and he died there on April 29, 1898.