When Elmer Timothy Thistlethwaite was born on 18 March 1862, in Centerville, Washington, Pennsylvania, United States, his father, Samuel Thistlethwaite, was 46 and his mother, Mary Farquhar, was 35. He married Elizabeth Eleanor Watkins on 2 February 1888, in Washington, Washington, Texas, United States. They were the parents of at least 2 sons and 4 daughters. He lived in Pennsylvania, United States in 1870 and East Bethlehem Township, Washington, Pennsylvania, United States in 1880. He died on 11 May 1943, in Centerville, Washington, Pennsylvania, United States, at the age of 81, and was buried in Centerville, Washington, Pennsylvania, United States.