| Common Name: | Lower Pannonia |
| Subdivision: | Province |
| Nation: | the Roman Empire |
| P1: | Pannonia |
| Flag P1: | Vexilloid of the Roman Empire.svg |
| S1: | Pannonia Secunda |
| Flag S1: | Vexilloid of the Roman Empire.svg |
| S2: | Pannonia Valeria |
| Flag S2: | Vexilloid of the Roman Empire.svg |
| Year Start: | 103 |
| Event End: | Reorganized |
| Year End: | 3rd century |
| Image Map Caption: | Pannonia Inferior (125 AD) |
| Capital: | Aquincum and Sirmium[1] |
| Today: | Bosnia and Herzegovina Croatia Hungary Serbia |
Pannonia Inferior, lit. Lower Pannonia, was a province of the Roman Empire. Its capital was Sirmium. It was one of the border provinces on the Danube. It was formed in the year 103 AD by Emperor Trajan who divided the former province of Pannonia into two parts: Pannonia Superior and Pannonia Inferior. The province included parts of present-day states of Hungary, Serbia, Croatia, and Bosnia and Herzegovina. The province was bordered to the east (across the Danube) by a Sarmatian tribe—the Iazyges. Later, the Vandals appeared to the north-east.
Major settlements in Pannonia Inferior included:
The province was yet again split during the reign of the tetrarchs into two more provinces, Pannonia Valeria in the north, with the new provincial capital at Sopianae, and Pannonia Secunda in the south with Sirmium as the provincial capital. During the Frankish period, in the 9th century, the term Lower Pannonia was used to designate eastern and southern regions of Pannonia, including the Slavic Principality of Lower Pannonia, particularly Posavina.
