The Tribal Hidage is a list of thirty-five tribes that was compiled in Anglo-Saxon England some time between the 7th and 9th centuries. It includes a number of independent kingdoms and other smaller territories, and assigns a number of hides to each one. The list is headed by Mercia and consists almost exclusively of peoples who lived south of the Humber estuary and territories that surrounded the Mercian kingdom, some of which have never been satisfactorily identified by scholars. The value of 100,000 hides for Wessex is by far the largest: it has been suggested that this was a deliberate exaggeration.

Mercia was one of the three main Anglic kingdoms founded after Sub-Roman Britain was settled by Anglo-Saxons in an era called the Heptarchy. It was centred on the River Trent and its tributaries, in a region now known as the Midlands of England.