The town of Dieburg was first named in 1492 in the tax books of the archbishopric of Hessen-Nassau. The city's name is derived from the Middle High German words diot, meaning "people," and burg, meaning "castle." Dieburg therefore refers to the castle of the people, located in the city center. The Dieburg Museum, located in the Fechenbach stately home, displays archeological findings. Of special interest is a relief of Mithras and a dyer's workshop. The coat of arms of the town Dieburg shows Martin of Tours. A cultural highlight is the yearly carnival, including a carnival parade that is completely based on honorary posts.
Dieburg lies in the Odenwald region of Germany. The Gersprenz (47 km), tributary to the Main, flows through Dieburg.