John M. Piles was born around 1840 in Ohio. His parents died when he was a child, and he was raised by family friends. By the early 1860s, he was working as a farmer in Preble County, Ohio. He enlisted in the Union army on October 30, 1861, and mustered in as a private in Company E of the 71st Ohio Infantry later that day. He took part in the Battle of Shiloh but fell gravely ill soon afterward. He eventually recovered and rejoined the regiment. He mustered out in San Antonio, Texas, on November 30, 1865.
Piles married Sarah E. Hamilton in Preble County, Ohio, on March 18, 1864, and they had at least two children: Oakleigh, born around 1867; and Lola, who was born in 1868 and died in 1871. By 1880, the family was living in Darke County, Ohio, and Piles was working as a painter. He applied for a federal pension on January 13, 1893, and eventually secured one. The family moved to Dayton, Ohio, sometime before 1900, and they were living in Cleveland, Ohio, by 1910. He died there on March 24, 1919. Sarah applied for a widow’s pension a few weeks later.