Owen Tudor in the context of "Mortimer's Cross"

The Tudors of Penmynydd (Welsh: Tuduriaid Penmynydd) were a noble and aristocratic family, connected with the village of Penmynydd in Anglesey, North Wales, who were very influential in Welsh (and later English) politics. From this family arose Sir Owen Tudor and thereby the Tudor dynasty, that ruled the Kingdom of England from 1485 to 1603. The Tudor dynasty ended in the early 17th century with the death of Elizabeth I.

The history of what is now Wales (Welsh: Cymru) begins with evidence of a Neanderthal presence from at least 230,000 years ago, while Homo sapiens arrived by about 31,000 BC. However, continuous habitation by modern humans dates from the period after the end of the last ice age around 9000 BC, and Wales has many remains from the Mesolithic, Neolithic, and Bronze Age. During the Iron Age, as in all of Britain south of the Firth of Forth, the culture had become Celtic, with a common Brittonic language. The Romans, who began their conquest of Britain in AD 43, first campaigned in what is now northeast Wales in 48 against the Deceangli, and gained total control of the region with their defeat of the Ordovices in 79. The Romans departed from Britain in the 5th century, opening the door for the Anglo-Saxon settlement. Thereafter, the culture began to splinter into a number of kingdoms. The Welsh people formed with English encroachment that effectively separated them from the other surviving Brittonic-speaking peoples in the early middle ages.

In the post-Roman period, a number of Welsh kingdoms formed in present-day Wales, including Gwynedd, Powys, Ceredigion, Dyfed, Brycheiniog, Ergyng, Morgannwg, and Gwent. While some rulers extended their control over other Welsh territories and into western England, none were able to unite Wales for long. Internecine struggles and external pressure from the English, and later the Norman conquerors of England, led to the Welsh kingdoms coming gradually under the sway of the English crown. In 1282, the death of Llywelyn ap Gruffudd led to the conquest of the Principality of Wales by King Edward I of England; since then, the heir apparent to the English monarch has borne the title "Prince of Wales". The Welsh launched several revolts against English rule, the last significant one being that led by Owain Glyndŵr in the early 15th century. In the 16th century Henry VIII, himself of Welsh extraction as a great-grandson of Owen Tudor, passed the Laws in Wales Acts aiming to fully incorporate Wales into the Kingdom of England.

Ednyfed Fychan ap Cynfrig (Welsh pronunciation: [ɛdˈnəvɛd ˈvəχan ap ˈkənvrig], died 1 October 1246) was a Welsh nobleman who became distain (roughly equivalent to the position of seneschal) of Gwynedd in north Wales. He served in this position under the princes of Gwynedd for almost thirty years. Ednyfed's tenure as distain appears to have coincided with the transformation of the office from one of domestic service to that of being the prince of Gwynedd's closest adviser and agent. He is recorded witnessing Llywelyn ab Iorwerth's charters, carrying out diplomatic missions, administering justice, and perhaps even leading military action on the prince's behalf. After Llywelyn's death in 1240, Ednyfed served in the same position under Llywelyn's son and successor Dafydd, and is repeatedly recorded leading diplomatic missions on Dafydd's behalf to his rebellious brother Gruffudd and Henry III. Ednyfed died some eight months after Dafydd, probably on 1 October 1246.

Ednyfed established a ministerial dynasty which would serve the princes of Gwynedd for over thirty years after his death until the Edwardian conquest. His preeminence allowed him to marry Gwenllian, a daughter of the Lord Rhys, prince of Deheubarth. Ednyfed's sons succeeded him as disteiniaid and his descendants held a monopoly on the position until the final campaign of Llywelyn ap Gruffudd in December 1282, the turning point of Edward I's conquest of Wales. Even after the Conquest, Ednyfed's heirs and the heirs of his brothers, known as the Wyrion Eden 'descendants of Ednyfed', enjoyed special privileges in their tenure first granted by the Llywelyns. They held their lands free from all renders other than military service, which allowed them to become very wealthy and influential. Ednyfed's descendants spread across Wales, and many served in the new English administration. Ednyfed's grandson Tudur Hen ap Goronwy established the branch of the family known as the Tudors of Penmynydd in Anglesey, which produced leading ecclesiastical and administrative figures of the fourteenth century in Wales. Owen Tudor, grandfather of Henry VII, was a member of this family, thus making Ednyfed the first distinguished ancestor of the House of Tudor.

Catherine of Valois or Catherine of France (27 October 1401 – 3 January 1437) was Queen of England from 1420 until 1422. A daughter of King Charles VI of France, she married King Henry V of England and was the mother of King Henry VI. Catherine's marriage was part of a plan to eventually place Henry V on the throne of France, and perhaps end what is now known as the Hundred Years' War. But, although her son Henry VI was later crowned in Paris, the war continued.

After Henry V's death, Catherine's unexpected marriage to Sir Owen Tudor helped lead to the rise of the House of Tudor's fortunes and to her Tudor grandson's eventual elevation to the throne as King Henry VII of England.