John W. Richtmyre was born around 1829 in Schoharie, New York, to Peter and Hannah Richtmyre. His father was a day laborer who owned $147 of real estate and $100 of personal property. The family lived in Broome, New York, and by 1850, he was working as a laborer. He married Harriet Haskins, and their daughter Ida was born around 1861.
He enlisted in the Union army on December 22, 1863, and he mustered in as a private in Company B of the 7th New York Heavy Artillery on December 29. According to his service records, he was 5 feet, 7 inches tall, with brown hair and blue eyes. The regiment took part in the Overland Campaign and the siege of Petersburg. He mustered out on August 1, 1865.
He returned to Broome after the war, and he earned a living as a farm laborer. By 1870, he owned $300 of real estate and $300 of personal property. He died in 1888.