Hermann Dornemann was born, as youngest of eight siblings, in Essen, district Altessen, on 27 May 1893. His family’s house was connected to the power system when he was aged eight. He was trained to become an engineer. During the World War I, he was wounded by a shot in his upper arm. In 1922, he moved to Ratingen and later to Düsseldorf. He retired in 1959. Dornemann and his wife had two children. Following his wife’s death in 1984, he moved to live with his daughter.

Being 110 years old, Dornemann was alert but blind since five years. He expressed sadness upon not being able to see his great-grandchildren. He was aware of being one of Germanys oldest living people; however, he also mentioned it was a burden to become that old. He was convinced his family cared about him too well when he was asked about his attitude. Dörnemann attributed his longevity to having a beer every day, but also avoiding sports and drinking the water of boiled potatoes, because of its vitamins.

Hermann Dornemann was considered to be the world’s oldest living man following the passing of 114 year-old Fred H. Hale on 19 November 2004, what was proven wrong with the validation of Emiliano Mercado del Toro of Puerto Rico, born in 1891.

Dornemann died of pneumonia in a hospital on 2 March 2005, at the age of 111 years, 279 days. He was preceded in death by his son who died in 2003 and by his daughter Rita, one grandchild and two great-grandchildren. He was succeeded as Germany’s oldest resident by 110 year-old Frieda Müller of Potsdam.