Rhiainfellt
| Rhiainfellt | |
|---|---|
| Born | unknown, flourished c. 630 |
| Died | unknown |
| Spouse | Oswiu |
| Issue | Alhfrith, possibly Alhflaed |
| House | Rheged |
| Father | 'Royth' (Rhaith) son of Rhun |
| Religion | Celtic Christianity |
Rhiainfellt, name variants including Rieinmelt and Rieinmelth, was a British princess of the royal house of the kingdom of Rheged, a part of the Hen Ogledd. Her name means "Lightning Maiden" or "Lightning Queen" in Old Welsh. She was a wife of Oswiu, King of Northumbria.