When William Cecil Nicodemus was born on 10 August 1878, in Hillsboro, Washington, Oregon, United States, his father, William Allen Nicodemus, was 29 and his mother, Clara Schmeltzer, was 20. He married Marie Kempf on 28 February 1904, in Reardan, Lincoln, Washington, United States. They were the parents of at least 1 son and 2 daughters. He lived in Spokane Falls, Spokane, Washington Territory, United States in 1880 and Spokane, Spokane, Washington, United States in 1920. He died on 3 March 1948, at the age of 69.