Shelley was born as Mary Katherine Sprunger in Berne, Indiana, USA, on 4 September 1909, to parents Reuben Sprunger and Laura Fuhrman. She was of Swiss and German descent. She had two brothers, Merrill and William. The family moved to Montana in 1912 and lived on a ranch at Shields, then on their homestead in Potter Basin. In 1916, they moved to Wilsall, then into Livingston in 1924.
Shelley graduated from Park County High School in Livingston and went on to attend Normal College (a 2-year school) where she earned a teaching certificate, graduating in 1929. She taught in rural schools and eventually in Livingston public schools until World War II, when she moved to Seattle and worked for Boeing on the B-17s as a “Rosie the Riveter”. After the war, she moved to California where she painted pottery and did wax carvings for jewelry. She returned to Montana in 1945 and continued with her teaching job.
In 1956, she married Clarence Shelley. The couple had no children together, but she raised her husband’s four children. She retired in 1968.
Kathryn Shelley died in Livingston, Montana, USA on 12 November 2021 at the age of 112 years, 69 days.
On 29 July 2021, following the death of Helen Self, she became the oldest (known) living person in the U.S. state of Montana, at the age of 111. On 17 August, she surpassed Self’s age, becoming the Montana’s oldest woman ever. At the time of death, she was the second-oldest (known) person who died in Montana, after Walter Breuning.
Her age was validated by LongeviQuest on 17 March 2023.