William Blantz was born around 1842 in Lancaster County, Pennsylvania, to Benjamin and Magdalena Blantz. His father was a carpenter who owned $1,700 of real estate and $180 of personal property by 1860. He grew up and attended school in Elizabeth Township, Pennsylvania. By the early 1860s, he was working as a farmer in Brickerville, Pennsylvania.
He enlisted in the Union army, and he mustered in as a private in Company B of the 79th Pennsylvania Infantry on September 5, 1861. According to his service records, he was 5 feet, 7 ¼ inches tall, with brown hair and dark eyes. The regiment took part in the Battle of Perryville, the Battle of Stones River, the Battle of Chickamauga, the Atlanta campaign, the March to the Sea, and the Carolinas campaign. He mustered out on July 12, 1865.
He enlisted in the Regular Army in October 1865, and he mustered in as a private in the 11th United States Infantry. He deserted on December 15, 1865. He returned to Elizabeth Township and resumed his work as a farmer. He married a woman named Elizabeth sometime before 1880. Their relationship, however, was tumultuous. According to a local writer, they suffered from an “incompatibility of temper,” and he “occasionally inflicted corporeal punishment on the one whom he had sworn to protect and cherish.” His wife “had him arrested” in the early 1880s, and he responded by “desert[ing] her.”
In 1890, a local court charged him with “desertion” and ordered him to pay $5 per week “for the support of his wife.” In February 1891, he was imprisoned and charged with adultery. According to a local writer, however, the “prosecutor failed to prove his charge and the case was dismissed.” He died in September 1896.