John Hawley was born around 1846 in New York. By 1860, he was living in Rosendale, Wisconsin, on the farm of Charles and Matilda Anderson. He enlisted in the Union army on October 22, 1861, and he mustered in as a private in Company A of the 2nd Wisconsin Cavalry later that day. The regiment took part in the siege of Vicksburg and the siege of Jackson. He died of disease in Hempstead, Texas, on September 25, 1865.