End of Rheged
After Bernicia united with Deira to become the kingdom of Northumbria, Rheged was annexed by Northumbria, some time before AD 730. There was a royal marriage between Prince (later King) Oswiu of Northumbria and the Rhegedian princess Riemmelth, granddaughter of Rum (Rhun), probably in 638, so it is probable that it was a peaceful takeover, both kingdoms being inherited by the same man.
After Rheged was incorporated into Northumbria, the old Cumbric language was gradually replaced by Old English, Cumbric surviving only in remote upland communities. In the 10th century, after the power of Northumbria was destroyed by Viking incursions and settlement, large areas west of the Pennines fell without warfare under the control of the British Kingdom of Strathclyde, with Leeds recorded as being on the border between the Britons and the Norse Kingdom of York. This may have represented the political assertion of lingering British culture in the region. The area of Cumbria remained under the control of Strathclyde until the early 11th century when Strathclyde itself was absorbed into the Scottish Kingdom. The name of the Cymry (Welsh people) has, however, survived in the name of Cumberland and now Cumbria.
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