See also

Iorwerth DRWYNDWN (1145-c. 1174)

1. Iorwerth DRWYNDWN, son of Owain Gwynedd, Prince of Gwynedd (c. 1100-1169), was born in 1145 in Aberffraw Castle, Inys Mon. He married Margred Ferch Madog circa 1163. He died circa 1174.


Margred Ferch Madog, daughter of Madog ap Maredydd ( - ) and Susanna Ferch Gruffydd ( - ), was born circa 1129. She and Iorwerth DRWYNDWN had the following children:



Llywelyn "Mawr" ap Iorwerth PRINCE OF NORTH WALES (1173-1240)

Second Generation

2. Llywelyn "Mawr" ap Iorwerth PRINCE OF NORTH WALES The Great, son of Iorwerth DRWYNDWN and Margred Ferch Madog, was born in 1173. He had the title 'Prince of North Wales'. He died in 1240. He married Gwenllian. He married Joan PLANTAGENET.


Llywelyn ap Iorwerth, Prince of North Wales also went by the nick-name of Llywelyn 'the Great'. He gained the title of Prince Llywelyn of North Wales. He hanged the Anglo-Norman baron, William de la Braose, for having an affair with his wife.

Nothing in the Middle Ages more weakened Wales’s chances of emerging as an independent state than the prevailing rules of inheritance. Instead of land and titles passing to the eldest son, everything was divided up among competing heirs. Although sharing laws, customs and language, seldom were the Welsh united under a single dominant ruler.

This was the situation faced by Llywelyn ap Iorwerth when he inherited one third of the ancient kingdom of Gwynedd. Yet by the age of 27 he was the most powerful figure in northern Wales. He defeated his uncle Dafydd in battle and, benefiting from the death of a cousin, took control of all of Gwynedd.

Llywelyn was as astute a political manipulator as any medieval prince. He befriended King John of England, assisted in his campaign against the Scots and married Joan, his illegitimate daughter. It all strengthened Llywelyn’s hand within Wales and helped him seize control of Powys and Ceredigion.

Known to history as a weak and vacillating ruler, John was not a dependable ally. He turned against Llywelyn and having marched into northeast Wales, defeated him in battle. It was the cue for the Welsh to rise up and unite behind Llywelyn.

John was also under internal pressure from his barons. The treaty of Magna Carta in 1215 led to a period of civil strife in England that yielded considerable dividends for Llywelyn. He regained control of the lands he had lost and marched his army into Shrewsbury.

Over the next three years Llywelyn extended his power base into the south, and circumscribed the authority of the Marcher Lords. He became unquestionably the single most powerful figure in Wales, a status recognised by the Treaty of Worcester in 1218.

More than just an opportunistic warlord, Llywelyn refined Wales’s laws and patronised its bards. On the shifting sands of Welsh medieval power politics, he laid strong foundations on which his grandson, Llywelyn ap Gruffudd would build.


Gwenllian was the daughter of Endyfed Fychan ( - ).


Joan PLANTAGENET was the daughter of John Lackland KING OF ENGLAND (1167-1216) and Isabelle Tallefer of Angouleme ( - ). She and Llywelyn "Mawr" ap Iorwerth PRINCE OF NORTH WALES had the following children:



Helen ( -aft1294)

Third Generation

3. Helen of Wales, daughter of Llywelyn "Mawr" ap Iorwerth PRINCE OF NORTH WALES The Great and Joan PLANTAGENET, died after [Julian] February 1294. She married Donald MAR.


Sir Donald MAR was born before 1252. He had the title '6th Earl of Mar'. He died after [Julian] 25 July 1297. He and Helen had the following children:



Isabella MAR ( -bef1302). Isabella had the title 'Lady of Mar'. She appeared in the census. She died before 1302.