Silas W. Baxter was born on September 17, 1833, in Middletown, Pennsylvania, to Daniel and Mary Baxter. He probably grew up and attended school in Middletown, and his father died sometime before 1850. By the early 1860s, he was working as a farmer.
He enlisted in the Union army on January 7, 1862, and he mustered in as a private in Company C of the 11th New York Cavalry. According to his service records, he was 5 feet, 8 inches tall, with auburn hair and blue eyes. The regiment was stationed around Washington, D.C., from May 1862 until March 1864. Union officials transferred the regiment to the Department of the Gulf in the summer of 1864. He was promoted to corporal in February 1863, and he mustered out on July 21, 1865.
He settled in Friendsville, Pennsylvania, after the war, and he married Hester Rutan on February 22, 1866. They had at least five children: Dennis, born around 1867; Jane, born around 1869; Mary, born around 1871; Lewis, born around 1874; and Oscar, born around 1879. He worked as a farmer and shoemaker, and by 1870, he owned $600 of real estate and $400 of personal property. He moved to Jessup, Pennsylvania, in the 1870s, and then to Harford, Pennsylvania, in the 1880s. He applied for a federal pension in December 1879 and eventually received one. By 1890, he was suffering from rheumatism. He moved to Montrose, Pennsylvania, in the 1890s, and he died there of gastric carcinoma on July 29, 1908.