Jonathan Butterworth was probably born on December 27, 1843, in Leicester, Massachusetts, to Jonathan and Eliza Butterworth. Her father was a spinner who owned $700 of real estate and $50 of personal property by 1860. He grew up in Leicester, and by 1860, he was working as a weaver.
He enlisted in the Union army on August 14, 1862, and he mustered in as a private in Company C of the 36th Massachusetts Infantry on August 27. According to his service records, he was 5 feet, 3 inches tall, with dark hair and black eyes. The regiment took part in the Battle of Fredericksburg, the siege of Vicksburg, the Overland Campaign, the siege of Petersburg, and the Appomattox campaign. He fell ill in September 1863, and he spent the next five months recovering. He mustered out on June 8, 1865.
He settled in Worcester, Massachusetts, after the war. He applied for a federal pension in March 1867 and eventually received one. He married Fannie J. Allen on November 2, 1870, and the couple had no children. They lived in Worcester, and he worked as a weaver. He died in Worcester in 1919.