John Mauch was born in Germany on December 24, 1888 and came to the United States as a child. One of fifteen children, he went into farming after completing grammar school. He served in the United States Infantry during World War I, and also worked in an army hospital. Following the war, Mauch returned to his family's farm where he grew potatoes, alfalfa, corn, and a variety of other crops. Maunch never married or had children and retired from farming at the age of eighty-three. He then went on to live with a niece for a number of years before moving into a Care Centre at the age of 105.
In his final years, Mauch became quite hard of hearing and had poor vision, but maintained a good appetite and was still able to carry on a conversation almost until the end. On his 110th birthday, the Community Liaison at his care centre said "John is very much at peace in his life. Doctors say he has a very strong heart and his attitude is always positive. He knows it's his birthday, but teases everyone about his age." Mauch outlived all 14 of his siblings and died on March 7, 1999 at the age of 110 years, 73 days.
According to his niece, Frances, "He loved nature and would teach us about the habits of the wild animals and birds that existed in the area. I also remember how he loved to play pinochle in the evenings. He was always so kind and gentle. He was such a considerate and thoughtful man and always so polite. You don't see people like him anymore." Another niece, Mary Bovee, echoed her sister's comments and said "John was such a good-natured man with a great sense of humor. When we were young children, he would entertain us by making shadow pictures on the walls and then he would whittle wood into various things, making us guess what he was creating."
John Mauch was validated by the Gerontology Research Group on 1 January 2006.