Mark Durant Knappe was born in Mt. Vernon on August 27, 1924 to Adam and Elizabeth (Hubbard) Knappe. He graduated from Mt. Vernon schools. He enlisted in the U.S. Army on December 4, 1945 and served at Fort Riley, Kansas and Fort Meade, Maryland in the 970th Counter Intelligence Corps Detachment. He was honorably discharged on January 2, 1947.
He was married twice, first to Frances and then to Dollie, but was widowed twice. He had four children, Esther, Mark, Elizabeth, and James, and several step-daughters.
Mark worked in construction for a time in Kansas, then returned to South Dakota and engaged in farming. However, much of his career was spent as a school custodian in Chamberlain, Mt. Vernon and Mitchell. He retired from this work in the late 1990s, remaining in Mitchell. He lived at Avera Brady Health and Rehab during the last years of his life. Mark was a kind and gentle man with a good sense of humor, and he was a good friend and relative to many people.
He was preceded in death by his parents, three brothers, Carl, Earl and Paul and two sisters.