Helicobacter pylori (H. pylori) is a spiral-shaped bacterium that inhabits the stomach lining of many individuals worldwide. Over the years, it has been strongly associated with a number of gastrointestinal disorders, including duodenal ulcers, gastric ulcers, and gastric cancer. The historical journey of the understanding of H. pylori and its role in gastric diseases has transformed medical knowledge, leading to new methods of diagnosis, treatment, and prevention. This article delves into the history of Helicobacter pylori, its connection to peptic ulcers, and its role in the development of gastric cancer.