Lleucu was the name of the wife of Llewelyn Bren (a.k.a. "Llewelyn of the Woods"), a minor Welsh nobleman of the late 13th and early 14th centuries who revolted against the English-appointed landowner of Glamorgan, Payn de Turberville of Coity. Lleucu fought alongside her husband (as did their sons), but they were unsuccessful. Llywelyn surrendered unconditionally, other than to plead that only he should be punished and his followers should be spared (this earned him the respect of the English lords). However, before he could be pardoned, Edward II's favorite, Hugh Despenser the Younger, unlawfully executed him, spurring more resentment (from both the Welsh and English people) that eventually lead to the overthrow of Edward II.After this, the sons of Llewelyn & Lleucu had the family lands restored to them; and succeeding Earls of Hereford continued to pay Lleucu an allowance until she died in 1349.Edit: corrected the centuries.
Based on the discussion in this thread [[https://www.behindthename.com/bb/fact/4918246]] it seems as though this usage is a modern imposition on a much older Welsh name of unknown original meaning. According to one poster (and supported by https://www.babynames.com/name/Lleucu), it's likely this name is a feminine version of the typically-masculine name 'Lleu' meaning 'light' + '-cu' meaning 'dear' in Welsh. [noted -ed]
It is a very beautiful, but uncommon name. I think it is a fabulous name, however, due to the Ll, the English speakers tend to have trouble with it.
― Anonymous User 1/1/2015
2
Cu means dear and beloved in Welsh, and lleu is old Welsh for bright/light, bright and dear would be the translation. It is not really a form of Lucia or Lucy except by coincidental fact of both names being derived from Indo-European languages which share common word origins.
Morfydd reports (13 September 2006) that: The database has got it wrong. The name is Lleucu. The "ll" is pronounced by putting your tongue where you would to say "l" and blowing. Having achieved that, the pronunciation is LLy-kee. [noted -ed]
After this, the sons of Llewelyn & Lleucu had the family lands restored to them; and succeeding Earls of Hereford continued to pay Lleucu an allowance until she died in 1349.
Edit: corrected the centuries.