James Calvin Adams was born in Morgan Count, Kentucky on December 11, 1846 to Lott William and Rebecca May Adams. He spent his childhood working on his family's farm. He was the third of eight children, and the oldest boy. His mother died in 1856 at the age of 32. His father died in 1861 at the age of 44, leaving Adams orphaned. After being imprisoned at the age of 16 during the Civil War he was released and settled in the Montana Territory in 1863. He spent several years working for the Diamond R. Wagon Co. hauling supplies from Fort Benton to Walla Walla via the Mullan Road. In December 1874, he moved to Sun River, Montana, where he established the Sun River Ranch. He raised cattle, horses, and sheep, which he sold to the U.S. Army at nearby Fort Shaw. He opened stores in Sun River and in Augusta, Montana and by 1882 was one of the wealthiest landowners in the area. Adams died in 1913.