The story of Culhwch and Olwen is a remarkable Welsh tale told in two manuscripts. Partially in The White Book of Rhydderch (Llyfr Gwyn Rhydderch) written in the mid-fourteenth century and in total in The Red Book of Hergest (Llyfr Coch Hergest) written later in the same century. Both contain a collection of the earliest Welsh prose texts. The story is included in a group of tales that was later known under the title The Mabinogion. Culhwch is connected with King Arthur who features in the tale and having been formulated prior to the 11th century is perhaps the earliest Arthurian tale. The stories draw from earlier pre-Christian Celtic mythology.
The White Book of Rhydderch is now located in the National Library of Wales and has been split into two volumes. One containing Christian scripts in Welsh translated from Latin and the other a collection of pre-Christian mythology. The Red Book of Hergest gets its name from its association with Hergest Court, where the Vaughan family had it in their possession, and the colour of its binding in leather. Written on vellum it is noted as an extremely important medieval Welsh manuscript and contains a collection of welsh poetry and prose. It is now located in Jesus College Oxford. The book gives an account of the story of Culhwch and Olwen a synopsis of which follows.
Central to the tale is Ysbaddaden Bencawr who was a massive giant who was known for being nasty and cruel. He lived in an inaccessible castle from where he ruled his domain. He has a daughter called Olwen and the fates foretell that should she ever marry, it will result in the death of Ysbaddaden. The hero Culhwch seeks to marry Olwen and in order to gain the consent of her father Ysbaddaden, he draws on the support of his cousin King Arthur.
The Welsh King Kylidd has a son, Culhwch. Culhwch’s mother Goleuddydd, daughter of Prince Anlawdd, becomes unstable during pregnancy, wandering the land and gives birth in a pig run. After the birth of Culhwch she regains her reason but dies soon afterwards. Before her death she tells King Kylidd to ensure no harm befalls Culhwch. The child is brought up in secret by a swineherd until coming of age. In the meantime the King marries the wife of King Doged who he had killed. The new Queen has a daughter by Doged who she brings with her to Kylidd’s court.
The Queen laments that she and King Kylidd have not produced a male heir but then learns of the existence of Culhwch. He is called to court and his new stepmother wants Culhwch to marry his step sister to guarantee succession. This Culhwch refuses to do. His stepmother is extremely offended and puts a curse on him which means he can only marry the daughter of Ysbaddaden, Olwen. His stepmother thinks he will be doomed never to marry as she knows Ysbaddaden will never allow this for fear of his own mortality.
Olwen is known to be very beautiful and Culhwch, although he has never seen her and under the influence of the spell, sets out to find her. On the advice of his father he seeks to enlist the help of his cousin King Arthur. Culhwch travels to Cornwall and Arthur’s court at Celliwig. King Arthur agrees to help Culhwch and sends out scouts to search for Olwen. After a year they are unsuccessful. Culhwch’s friend Cei suggests they go to look for Olwen alone, but Arthur then provides six warriors (Cai, Bedwyr, Gwalchmei, Gwrhyr, Menw and Cynddylig) to help Culhwch find Olwen.
In his quest to find Olwen Culhwch meets a shepherd named Custennin. Custennin is married to Culhwch’s mother’s sister and they have a serious grievance against Ysbaddaden. The cruel and vicious giant had robbed Custennin of his lands and murdered twenty-three of his twenty-four children, leaving only his son Goreu alive. Goreu then joined Culhwch and Arthur’s warriors on the quest.
Custennin and his wife arrange for Culhwch to meet Olwen whereupon she agrees to lead him to her father’s castle. After a battle in which Ysbaddaden attempts to kill Culhwch, but is himself wounded, the giant agrees to Culhwch’s marriage to his daughter Olwen. However, the wily giant knows that his death is foretold should Olwen ever marry and is determined this should never happen. He stipulates that the betrothal is only agreed if Culhwch first completes a number of tasks. These tasks are so onerous that Ysbaddaden cannot believe that Culhwch will succeed in completing them.
Culhwch and his party set out on the tasks, most of which relate to the ceremonial cutting of Ysbaddan's hair and shaving him. In order to do this he needs to locate Wyrnach the giant whose sword is needed to kill Twrch Twrch. Twrch Twrch is an Irish King now turned into a boar by a curse. On his head between his ears is stored a comb, razor and scissors. These are required in order for Culhwch to complete the ceremonial task of cutting Ysbaddaden’s hair. To get the sword Culhwch’s friend Cei persuades Wyrnach to let him have the sword so he can sharpen it. This was a trick and Cei takes the sword and then cuts off his head.
In order to hunt down Twrch Twrch Culhwch is required to use the hound Drudwyn. The only person known to be able to control the hound is Mabon ap Madron, who at the time was imprisoned in a prison in Gloucester. With the help of the wisest animals in the land including the ancient Salmon of Llyn Llyw they find Mabron who is freed. They then track down Ysgithyrwyn the great boar (secondary to Twrch Twrch) that is killed by Arthur’s own dog Cafall. They take one of his tusks which is also necessary for the grooming of Ysbaddaden.
Culhwch’s party then go on the trail of Twrch Twrch. It is a long arduous journey covering a wide area, but ultimately the rest of the implements for cutting and shaving Ysbaddaden are gained from Twrch Twrch who is then driven into the sea off the Cornish coast. Finally King Arthur then kills the Black Witch whose blood is required to soften the beard of the giant before shaving. Going back to the castle of Ysbaddaden their remaining deed is to cut the giants hair and shave him. After this is done Culhwch is free to marry Olwen and Ysbaddaden dies.