The Ingle family papers center around Olive Ingle, the daughter of Thornton D. Ingle, a Free Methodist minister who rode a circuit in the Maumee River valley from the 1870s until about 1920. Thornton Ingle was from a line of ministers. His father, the Reverend Isaac Ingle, was also an itinerant preacher of the United Brethren Church, and was a pioneer rider in the Maumee River Valley circuit. His son I. Ingle also followed the family's clerical calling.
Olive's mother, Margaret Cowdrick Ingle, was the daughter of Joseph and Margrat Cowdrick, settlers in Henry County Ohio. Margaret married Thornton D. Ingle on March 30, 1857. Olive was born in Marion, Ohio in 1863, and the young family frequently moved from one farm to another, always staying within Ohio. Olive had eight brothers and sisters, two of whom died in infancy, and she married James Bortel on December 7, 1889.