King of Wales was a very rarely used title, because Wales never achieved the degree of political unity that England or Scotland did. However, in the mid-11th century, one of the Welsh kings, Gruffydd ap Llywelyn, gained supreme power: "in 1055 he absorbed Deheubarth (i.e., southern Wales) as well, thus becoming in effect King of Wales"[1]. Historian John Davies states that Gruffydd was "the only Welsh king ever to rule over the entire territory of Wales... Thus, from about 1057 until his death in 1063, the whole of Wales recognised the kingship of Gruffudd ap Llywelyn. For about seven brief years, Wales was one, under one ruler, a feat with neither precedent nor successor."[2]

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