Pannonia was a province of the Roman Empire located in the central part of Europe, primarily in what is now western Hungary, eastern Austria, northern Croatia, and parts of Slovenia and Serbia. Established in the 1st century AD, it served as an important military and administrative region, facilitating trade and communication across the empire. The province was known for its diverse population, including Celts, Illyrians, and later Romans. Pannonia was characterized by fertile land and significant urban centers, such as Aquincum and Sopianae, which contributed to its economic prosperity during Roman rule.