John Nelson Hastings was born on March 21, 1838, in Grantham, New Hampshire, to William Hastings and Mary Hart. His father was a farmer who owned $700 of real estate and $300 of personal property by 1860. Hastings grew up and attended school in Grantham, and by 1860, he was working as a machinist. He married Mary Elizabeth Corliss in the early 1860s, and they had at least two children: George, born around 1864; and Edna, born around 1876. They lived in Grantham, New Hampshire, and Hastings worked as a farmer. By 1870, they owned $300 of personal property. He died in Grantham on August 14, 1892.