Guernsey was born Sarah Elizabeth Mitchell in 1860 in Salem, Ohio to Daniel P. Mitchell and Ann Eliza Baker.[1] Her great-great-grandfather, Rev. John Mitchell, served as a private in the Virginia Militia and in Captain James Pendelton's company in the First Continental Artillery during the American Revolutionary War.[1] She was also a descendant of Rev. Anthony Jacob Henkel, who came to the colonies in 1717 as one of the founders of the Lutheran Church in America.[1]
Adult life
After graduating from the Kansas State Normal School, Guernsey worked as a schoolteacher for four years.[1] In 1879, she moved to Independence, Kansas to serve as principal of the local high school.[1]
She was elected President General of the National Society Daughters of the American Revolution and served in that position from 1917 to 1920.[2] During her first week in office, she formed the War Relief Service Committee.[2] She traveled around the country attending many state conferences and chapter meetings of the DAR, including meetings in 41 states, Cuba, France, and England.[3] She traveled to France following World War I, visiting Tilloloy, where the DAR would rebuild the municipal water system.[3] She was the first president general of the DAR to visit Alaska.[3]