奥斯特拉西亚由法兰克王国墨洛温王朝东北部分构成，领土包括今天法国东部、德国西部、比利时，卢森堡和荷兰的领土。其首都为梅斯作为，虽然有些国王在兰斯，特里尔和科隆统治。奥斯特拉西亚也被用来指代意大利东北部，相对于纽斯特里亚指代西北部。

Austrasia is a territory which formed the northeastern section of the Merovingian Kingdom of the Franks during the 6th to 8th centuries.

Austrasia, centred on the Middle Rhine and the Moselle rivers, was the original territory of the Frankish tribes prior to their unification under Clovis I. In AD 567, it became a separate kingdom within the Frankish Empire and was ruled by Sigebert I. It eventually lost its territorial character in the Carolingian Empire in the 8th century.