Helicobacter pylori (H. pylori) is a microorganism that is highly prevalent in mankind and closely linked to several gastroduodenal disorders. Though Helicobacter pylori was introduced to the scientific community in 1983 by Robin Warren and Barry Marshall, a closely related Helicobacter species had been described one hundred years earlier by the Italian pathologist Giulio Bizzozero in the canine stomach. In this review we analyze the different steps involved in the discovery of Helicobacter species and provide a biography of the pioneer Giulio Bizzozero.