When Joseph Patrick Mellmer was born on 15 November 1898, in Lefor, Stark, North Dakota, United States, his father, Joseph Mellmer, was 43 and his mother, Elisabeth Rinshenk, was 36. He married Elizabeth Krebs on 24 May 1920, in Lefor, Stark, North Dakota, United States. They were the parents of at least 3 sons and 2 daughters. He lived in Dickinson, Stark, North Dakota, United States in 1900 and Havelock, Hettinger, North Dakota, United States in 1920. He died on 7 April 1979, in Roseville, Placer, California, United States, at the age of 80, and was buried in Sacramento, Sacramento, California, United States.