John Miller Barhan was born around 1842 in Indiana to Stephen and Rebecca Barhan. His father was a farmer who owned $1,000 of real estate and $300 of personal property by 1860. He grew up and attended school in Jefferson, Indiana.
He enlisted in the Union army on September 24, 1861, and he mustered in as a private in Company F of the 30th Indiana Infantry. The regiment took part in the Battle of Shiloh, the siege of Corinth, the Battle of Chickamauga, and the Atlanta campaign. He eventually earned a promotion to sergeant, and he mustered out on November 25, 1865.
He settled in Marion County, Oregon, after the war, and he earned a living as a farmer. He supported the Democratic Party in the election of 1866. He married a woman named Sarah around 1868, and they had at least three children: Mary, born around 1870; John, born around 1875; and Sherman, born around 1879. He applied for a federal pension in March 1883 and eventually received one. His wife died on April 19, 1905. By 1910, he was living in his daughter Mary’s household in Brownsville, Oregon. He died there of pneumonia on March 14, 1911.