Jacob McGinley Wilhelm was born on February 5, 1838, in Pennsylvania to Jacob Wilhelm. His father was a farmer who owned $5,000 of real estate and $1,000 of personal property by 1860. Wilhelm grew up and attended school in Metal, Pennsylvania, and by 1860, he was working as a teacher.
He enlisted in the Union army on August 9, 1862, and he mustered in as a corporal in Company H of the 126th Pennsylvania Infantry later that day. He took part in the Battle of Fredericksburg and the Battle of Chancellorsville. He mustered out in Harrisburg, Pennsylvania, on May 20, 1863. He enlisted again on August 30, 1864, and he mustered in as a private in Company B of the 203rd Pennsylvania Infantry. He was eventually promoted to corporal, and he mustered out on June 22, 1865.
Wilhelm returned to his father’s household in Metal after the war, and by 1870, he was working as a farm laborer. He married a woman named Catherine in the early 1870s, and they had at least seven children: John, born around 1873; Annie, born around 1875; Thomas, born around 1878; Emma, born around 1879; Mary, born around 1881; Helen, born around 1883; and Harrison, born around 1888. They lived in Metal. His wife died sometime in the late 1800s. He remained in Metal for the rest of his life, and he died there of “senility” on December 30, 1921.