1136 Richard Fitz Gilbert de Clare was ambushed and killed on April 15. "According to the Gesta Stephani, on Stephen's accession Clare offered him his allegiance in return for unspecified but large grants. On the new king's refusal at what would have been his great Easter court of 22 March 1136, Richard headed with a large household for Ceredigion, allegedly to stir up war against the king. On the way he was ambushed by a party of Welsh headed by one or other or both of the brothers, Morgan and Iorwerth ab Owain, lords of Gwynllwg, and killed on 15 April. Gerald of Wales gives the traditional place of the murder as 'Coed Grono', probably the deep and forested pass of the Grwyne Fawr between Abergavenny and Talgarth. His body was taken to Gloucester Abbey for burial." [1]
[1] David Crouch, "Clare, Richard de (d. 1136)," Oxford Dictionary of National Biography (Oxford University Press, 2004, online edition), [Oxford_Dictionary_National_Biography], [OxfordDNB(UM)].