Iorwerth mab Owain Gwynedd (or Iorwerth Drwyndwn meaning "the flat-nosed"),  (c. 1130–1174), was the eldest legitimate son of Owain Gwynedd (the king of Gwynedd) and his first wife Gwladys (Gladys) ferch Llywarch. He married Marared ferch Madog. His son, Llywelyn the Great,  eventually united the realm and became known as Llywelyn Fawr and is one of Wales's most famous monarchs. Iorwerth received Nant Conwy as his inheritance from his father, Owain Gwynedd.  However, he did not receive the crown succession, as was the normal tradition, because of his nose defect (his sobriquet 'Trwyndwn' means broken-nosed). 
Llywelyn the Great was a King of Gwynedd in north Wales and eventually "Prince of the Welsh" and "Prince of Wales". By a combination of war and diplomacy he dominated Wales for 45 years.
Owain ap Gruffudd was King of Gwynedd, North Wales, from 1137 until his death in 1170, succeeding his father Gruffudd ap Cynan. He was called Owain the Great and the first to be styled "Prince of Wales". He is considered to be the most successful of all the North Welsh princes prior to his grandson, Llywelyn the Great. He became known as Owain Gwynedd to distinguish him from the contemporary king of Powys Wenwynwyn, Owain ap Gruffydd ap Maredudd, who became known as Owain Cyfeiliog.
Sir Owen Tudor was a Welsh courtier and the second husband of Queen Catherine of Valois (1401–1437), widow of King Henry V of England. He was the grandfather of Henry VII, founder of the Tudor dynasty.
Gruffudd ap Cynan, sometimes written as Gruffydd ap Cynan, was King of Gwynedd from 1081 until his death in 1137. In the course of a long and eventful life, he became a key figure in Welsh resistance to Norman rule, and was remembered as King of all the Welsh and Prince of all the Welsh.
The Kingdom of Gwynedd was a Welsh kingdom and a Roman Empire successor state that emerged in sub-Roman Britain in the 5th century during the Anglo-Saxon settlement of Britain.
The Kingdom of Powys was a Welsh successor state, petty kingdom and principality that emerged during the Middle Ages following the end of Roman rule in Britain. It very roughly covered the northern two-thirds of the modern county of Powys and part of today's English West Midlands. More precisely, and based on the Romano-British tribal lands of the Ordovices in the west and the Cornovii in the east, its boundaries originally extended from the Cambrian Mountains in the west to include the modern West Midlands region of England in the east. The fertile river valleys of the Severn and Tern are found here, and this region is referred to in later Welsh literature as "the Paradise of Powys".
Dafydd ab Owain Gwynedd was Prince of Gwynedd from 1170 to 1195. For a time he ruled jointly with his brothers Maelgwn ab Owain Gwynedd and Rhodri ab Owain Gwynedd.
Gwenllian ferch Gruffydd was Princess consort of Deheubarth in Wales, and married to Gruffydd ap Rhys, Prince of Deheubarth. Gwenllian was the daughter of Gruffudd ap Cynan (1055–1137), Prince of Gwynedd and Angharad ferch Owain, and a member of the princely Aberffraw family of Gwynedd. Gwenllian's "patriotic revolt" and subsequent death in battle at Kidwelly Castle contributed to the Great Revolt of 1136.
Hywel ab Owain Gwynedd, Prince of Gwynedd in 1170, was a Welsh poet and military leader. Hywel was the son of Owain Gwynedd, prince of Gwynedd, and an Irishwoman named Pyfog. In recognition of this, he was also known as Hywel ap Gwyddeles. Hywel is also known as the Poet Prince for his bardic skills.
Bleddyn ap Cynfyn, sometimes spelled Blethyn, was an 11th-century Welsh king. Harold Godwinson and Tostig Godwinson installed him and his brother, Rhiwallon, as the co-rulers of Gwynedd on his father's death in 1063, during their destruction of the kingdom of their half-brother, Gruffydd ap Llywelyn. Bleddyn became king of Powys and co-ruler of the Kingdom of Gwynedd with his brother Rhiwallon from 1063 to 1075. His descendants continued to rule Powys as the House of Mathrafal.
Maelgwn ab Owain Gwynedd was a prince of part of Gwynedd. Little is known about him, but he was the son of Owain Gwynedd and Gwladus ferch Llywarch ap Trahaearn, and therefore full brother to Iorwerth Drwyndwn, the father of Llywelyn the Great. On the death of Owain Gwynedd in 1170, Maelgwn received Anglesey as his share of the kingdom, but in 1173, his brother Dafydd ab Owain Gwynedd attacked him and forced him to flee to Ireland. He returned later that same year, but was taken prisoner by Dafydd. There is no further record of his fate.
Madog ap Maredudd was the last prince of the entire Kingdom of Powys, Wales and for a time held the Fitzalan Lordship of Oswestry.
Ednyfed Fychan, full name Ednyfed Fychan ap Cynwrig, was a Welsh warrior who became Seneschal to the Kingdom of Gwynedd in Northern Wales, serving Llywelyn the Great and his son Dafydd ap Llywelyn. Ednyfed claimed descent from Marchudd ap Cynan, Lord of Rhos, 'protector' of Rhodri Mawr, King of Gwynedd. He was the ancestor of Owen Tudor and thereby of the Tudor dynasty.
Maredudd ap Cynan was the grandson of Owain Gwynedd, a king of Gwynedd and ruler of most of Wales in the 12th century. His father Cynan ab Owain Gwynedd held the title "Lord of Meirionnydd".
Llywarch ap Llywelyn was an important medieval Welsh poet. He is also known by his bardic name, "Prydydd y Moch".
The Battle of Aberconwy or the Battle of the Conwy Estuary was fought in 1194 between the forces of Llywelyn ap Iorwerth and his uncle Dafydd ab Owain Gwynedd for control of the Kingdom of Gwynedd.
The Royal House of Aberffraw was a cadet branch of the Kingdom of Gwynedd originating from the sons of Rhodri the Great in the 9th century. Establishing the Royal court of the Aberffraw Commote would begin a new location from which to rule Wales. The cadet branch achieved the recognised titles of Prince of Wales, King of Wales and were sometimes named King of Aberffraw.
The Royal House of Mathrafal began as a cadet branch of the Welsh Royal House of Dinefwr, taking their name from Mathrafal Castle, their principal seat and effective capital. They effectively replaced the House of Gwertherion, who had been ruling the Kingdom of Powys since late Roman Britain, through the politically advantageous marriage of an ancestor, Merfyn the Oppressor. His son, King Bleddyn ap Cynfyn, would join the resistance of the Anglo-Saxon King Harold Godwinson, against the invasion of William the Conqueror, following the Norman conquest of England. Thereafter, they would struggle with the Plantagenets and the remaining Welsh Royal houses for the control of Wales. Although their fortunes rose and fell over the generations, they are primarily remembered as Kings of Powys and last native Prince of Wales.
Senana ferch Caradog (c.1198–1263) was the wife of Gruffudd ap Llywelyn Fawr (1198–1244). Senana's full name was Senana ferch Caradog ap Thomas ap Rhodri ab Owain Gwynedd therefore Owain Gwynedd was her great great grandfather, although she came from an illegitimate line. She had four sons: Owain, Llywelyn, Dafydd and Rhodri. Additionally she had two known daughters: Gwladus and Margaret. Although it is unknown exactly when she died, she was buried in 1263 in Llanfaes.