King of the Britons

The title King of the Britons (Welsh: Brenin y Brythoniaid, Latin: Rex Britannorum) was used (often retrospectively) to refer to a ruler, especially one who might be regarded as the most powerful, among the Celtic Britons, both before^[1] and after^[2] the period of Roman Britain up until the Norman invasion of Wales and the Norman conquest of England. Britons were the Brittonic-speaking (ancestral language of Welsh) peoples of what is now Wales, England and southern Scotland. The Britons contributed as ethnic ancestors of the native British population including the Welsh, Cornish, and Scottish people but also of the Bretons.^[3]

During the Norman and Plantagenet periods, only Wales (or parts thereof) remained under Brittonic rule in Britain and the term "Britons" (Brythoniaid, Britaniaid, Brutaniaid) was used in Britain to mean the Welsh people (Cymry in modern Welsh). This, and the diminishing power of the Welsh rulers relative to the Kings of England, is reflected in the gradual evolution of the titles by which these rulers were known from "King of the Britons" in the 11th century to "Prince of Wales" in the 13th.^[2]

Name	Depiction	Reign	Regional power base	Recorded title or description	Source	Notes
Kings prior to this period are generally regarded as fictional Legendary Kings of Britain
Cassivellaunus (Welsh: Caswallawn fab Beli)		54BC
Tasciovanus		20 BC – 9 AD
Cunobeline (Welsh: Cynfelyn)		9 – 40	lands of the Trinovantes and Catuvellauni	King of the Britons	Suetonius, Dio Cassius	perhaps retrospective
(Roman rule from 43 to 410 AD)
Tiberius Claudius Cogidubnus / Togodumnus		40–43	lands of the Regni, Atrebates, and Belgae	Great King of the Britons (or perhaps: Great King of Britain)	marble inscription at Chichester	contemporary, self-description
(post-Roman, from 410 AD)
Vortigern (Welsh: Gwrtheyrn)		mid-5th century	unknown, but traditionally Powys	King of the Britons (in c. 449)	Bede	probably retrospective
Riothamus		c. 469	unknown, but active in Gaul	King of the Britons (in c. 469)	Jordanes	may refer only to Britons in Gaul
Ambrosius Aurelianus (Welsh: Emrys Wledig)		late 5th century	probably in the south	Leader [of the Britons]	Gildas	near contemporary
Natanleod		?-508			Anglo Saxon Chronicle	Possibly never even existed.
unnamed		c. 545	unknown	King over them [the Britons]	Procopius[4]	contemporary but distant
Maelgwn Gwynedd		?–549?	Gwynedd	King [who] reigned among the Britons	Historia Brittonum	retrospective
Selyf ap Cynan		?– c. 613	Powys	King of the Britons (in c. 613)	Annals of Ulster	near contemporary
Ceretic of Elmet (Welsh: Ceredig ap Gwallon)		c. 614 – 617	Elmet	King of the Britons (in 614)	Bede	may refer only to Britons in Elmet
Cadwallon ap Cadfan		?–634	Gwynedd	(Cadwalla,) King of the Britons (in 633)	Bede
Idris ap Gwyddno		?–635	unknown. perhaps Meirionnydd	King of the Britons (in 635)	Annals of Ulster (sub anno 633)[5]	perhaps Idris Gawr
Eugein I of Alt Clut		c. 642	Strathclyde	King of the Britons (in 642)	Annals of Ulster
Rule within the modern territory of Wales only
Cadwaladr		c. 654 – c. 664	Gwynedd	[King who] reigned among the Britons	Historia Brittonum	retrospective
Ifor		683–698	Llydaw (Brittanny)	"Sovereignty of the Britons"	Brut y Tywysogion[6]
Rhodri Molwynog		c. 712 – 754	Gwynedd	King of the Britons (in 754)	Annales Cambriae	perhaps retrospective
Use of King of Wales title begins (King of the Britons title continues also)
Cynan Dindaethwy		798–816	Gwynedd (insecurely from 754)	King of the Britons (in 816); The King (in 816) "King of all Wales" (Welsh: "Brenin Cymry oll"[7]	Annals of Ulster; Annales Cambriae
Merfyn Frych		825–844	Gwynedd	King of the Britons (in 829); Glorious King of the Britons	Historia Brittonum; Bamberg Cryptogram	contemporary
Rhodri Mawr (Rhodri the Great) (Welsh: Rhodri ap Merfyn		844–878	Gwynedd, from 854 also Powys, from 872 also Seisyllwg	King of the Britons (in 878) "began to reign over the Welsh" (843 AD)[8]	Annals of Ulster
Anarawd ap Rhodri		878–916	Gwynedd	King of the Britons (in 916) "ruled over all Wales" (900 AD)[9]	Annales Cambriae
Idwal Foel ap Anarawd		916–942	Gwynedd	King of the Britons (in 927)	William of Malmesbury
Hywel Dda		942–950	Deheubarth (from 920), from 942 also Gwynedd and Powys	King of the Britons (in 950) "King of all Wales" (Welsh: "Brenin Cymry oll"[10]	Annals of Ulster and Annales Cambriae
Dyfnwal ab Owain		930s–970s	Strathclyde	King of the Britons (in 973)	Annals of Ulster
Maredudd ab Owain		986–999	Deheubarth and Gwynedd and Powys	King of the Britons (in 999)	Brut y Tywysogion
Llywelyn ap Seisyll		1018–1023	Gwynedd and Powys; from 1022 also Deheubarth	King of the Britons (in 1023) "took the government upon himself...in his time the country of Wales was twelve years without war" "sovereignty of Wales"[11]	Annals of Ulster
Iago ab Idwal		1023–1039	Gwynedd and Powys	King of the Britons (in 1039)	Annals of Ulster
Gruffydd ap Llywelyn		1039–1063	Gwynedd and Powys, from 1057 also the rest of Wales	King of the Britons (in 1063; in 1058) Rex Walensium ("King of Wales")[12]	Annals of Ulster; Brut y Tywysogion
Bleddyn ap Cynfyn		1063–1075	Gwynedd and Powys and Seisyllwg	Support[er of] the whole Kingdom of the Britons (in 1075); Chiefest of the Britons	Brut y Tywysogion (sub anno 1173; sub anno 1113)
Rhys ap Tewdwr		1079–1093	Deheubarth (insecurely until 1081)	[Upholder of the] Kingdom of the Britons (in 1093)	Brut y Tywysogion
Use the title of Prince of Wales begins (King of Wales title continues also)
Gruffudd ap Cynan		1136–1137	Gwynedd (insecurely from 1081)	King of all the Welsh (in 1137)	Brut y Tywysogion
Owain Gwynedd		1137–1170	Gwynedd	Prince over the British nation (in 1146); King of Wales, King of the Welsh, Prince of the Welsh	Brut y Tywysogion; contemporary charters[13]

• Bretwalda
• List of legendary kings of Britain
• Pendragon