In his Celtic and Anglo-Saxon Kingship Professor D. A. Binchy reconsidered the early (pre-Norman) Welsh law of succession and concluded that ‘it was recast after the Anglo-Saxon model’. In his view the matter turned on two questions which have an important bearing on both Welsh and English history. When did the ‘Common Celtic’ type of kingship, in which a successor could be drawn from a four-generation group, give way in Wales to a system in which ‘the reigning king nominates his successor, who will normally be his son and only in exceptional circumstances his brother or paternal nephew’, and in particular what is the evidence provided on this point by the Welsh laws? Was the Anglo-Saxon ætheling the model for this Welsh constitutional innovation? It is my purpose in the present paper to discuss the position of the ætheling in matters of royal succession during the Anglo-Saxon period. Consideration of the relevance of these findings to Welsh history and law will be reserved for an article to be published elsewhere.