Nathaniel Moody Ilsley was born on August 25, 1837, in Newbury, Massachusetts, to Paul and Mary Ilsley. His mother died in 1846, and his father passed away in 1848. By 1850, he was living with his siblings in Newbury. By the 1855, he was working as a farmer, and by 1860, he owned $2,000 of real estate and $300 of personal property.
He enlisted in the Union army on July 23, 1862, and he mustered in as a private in Company I of the 35th Massachusetts Infantry on August 16. The regiment took part in the Battle of Antietam, the Battle of Fredericksburg, the siege of Vicksburg, the Knoxville campaign, and the Overland Campaign. On June 6, 1864, during the Battle of Cold Harbor, he was shot in the face and lost his left eye. He apparently rejoined the regiment on October 13, 1864, and he mustered out on June 9, 1865.
Ilsley returned to Newbury after the war, and he married Mary Hale there on May 14, 1868. Their son Daniel was born around 1872. He worked as a farmer in Newbury, and by 1870, he owned $4,100 of real estate and $700 of personal property. His wife died in 1906. By 1910, he was living in his son’s household in Newbury. He died there of chronic myocarditis on September 9, 1912.