As far as the medieval Arthurian stories (from the 12th until the 15th century) is concerned, one can make a rough distinction between two types: The first one is the episodic novel in verse, in which the hero often starts his quest from Arthur's court and returns there after his mission is completed, which usually does not take more than two years. Chrétien de Troyes poems have been imitated widely in medieval Europe, but have never been surpassed, partly because the imitators lacked his subtle use of irony and mystification. In his courtly vision the love between Lancelot and Guinevere was not yet burdened with guilt and the Grail was not yet the cup of Christ. (More about Chrétiens work further down). The second type is the chronicle in prose, in which the rise and fall of the kingdom is depicted. This is where the celebration of courtly love is overruled by Christian ethics. The story does not evolve around one or two heroes, but is a mixture of many different story-lines, all tied together, not unlike modern soap operas. There is however one difference, the Arthurian chronicles actually have a point to them; the events lead up to the death of Arthur and the decay of civilisation, triggered by sins like adultery and incest. We are left with some hope though: Arthur is carried away to the isle of Avalon and rumour has it that he will return.

The most important Arthurian chronicle of the thirteenth century is the Lancelot en Prose, also called the Vulgate Cycle. (More about this chronicle further down). Supernatural phenomena are present in both the poems, in which the fantasy of the old Celtic fairy-tales is still recognisable, and the chronicles, in which the wondrous world has a more Christian connotation.
The last of the medieval Arthurian writers is Thomas Malory, whose Morte Dartur seems like one big rčsume of all the previous writings about king Arthur and his knights. His work is usually the starting point for modern Anglo-Saxon versions of the legend. (More about Malory further down).

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Lancelot Crosses the Swordbridge and Lancelot imprisonned in Gorre (from Lancelot du Lac, French, early fourteenth century)

In many different versions of the legend Lancelot crosses the swordbridge in pursuit of Guinevere who is abducted by an evil knight. In Chrétiens Chevalier de la Charette it shows how far he is willing to go in the name of love. In the Vulgate Cycle it is embedded in many other adventures and Lancelots love Guinevere is tainted with guilt.

Malory mentions the abduction in his Morte Dartur, but not the swordbridge, either because he was in a hurry to tell the story and left out lots of details or because he thought crossing a bridge as sharp as a razorblade was just too improbable.
The abduction of the queen is still part of the action in several modern versions of the legend, with a little imagination one can even detect a faint echo of the swordbridge story in the movie First Knight.

Galeholt watches the lovers (Lancelot and Guinevere) first kiss as the seneschal and ladies converse.
ca 1315, Pierpont Morgan Library 805, f. 67
For the same scene in a different manuscript, click: And search for the First Kiss

The Lancelot en Prose is a comprehensive trilogy (Lancelot Propre, La Queste del Saint Graal and La Mort de Roi Artu), which was written between 1215 and 1230. It was copied often, by hand, a real monk's work (but by that time the secular prductions were mostly done by craftsmen in proffesional workshops). If you want to see an example, click here. In most manuscripts the Lancelot trilogy was preceded by two other stories: L'Estoire del Saint Graal and Merlin. This compilation is often called the Vulgate Cycle:
 

L'Estoire del Saint Graal:
"About the descendants of Joseph of Arimathea, who take the Holy Grail (the cup of Christ) with them to Britain, where they build the Grail-castle, in which the long line of Fisher Kings will live, as the keepers of the Grail."

Vulgate Merlin:
"The devil's son Merlin (but his mother is a true Christian and therefore the child is not evil) is Uther Pendragon's confidant and advises the construction of a Round Table. One seat at the table, the Perilous Seat, is meant for a chosen knight, and until this knight arrives nobody is to be seated there, for this person will surely die.

Uther develops a raging passion for Ygraine, the wife of the Duke of Gorlois. With the aid of Merlin's magic Uther makes love to Ygraine and thus Arthur is conceived. The child grows up as stepbrother to Kay. His descent remains a secret until Arthur is the only one capable of drawing the sword from the stone. He is crowned king and has to fight a lot of battles against the Saxons and rebellious vassals. Merlin's advice and magic are on his side.

Arthur marries Guinevere and her father gives him the Round Table as a marriage-gift. Merlin falls in love with the fairy Niniane and teaches her all his magic. But when she is fully-qualified, she locks him up in a tower from which there is no escape."

Lancelot Propre:
"Niniane raises the infant Lancelot in her realm beneath a lake, that is why his name is Lancelot du Lac (Lancelot of the Lake). As a young man he receives knighthood at king Arthur's court and falls in love with Guinevere the moment he sees her. He rides out, has adventures and meets his best friend Galehout, who initiates the first rendezvous between Lancelot an Guinevere." (Click here for an image)

During one of his adventures Lancelot is captured by the fairy Morgan, Arthur's half-sister. Several knights of the Round Table undertake quests to find him, but to no avail. Galehout is convinced his friend is dead and dies from sorrow. Morgan's magic can not extinguish Lancelot's love for Guinevere. When she understands it is no use, she lets him go.

Meanwhile Guinevere has been captured by Meleagant and Lancelot sets out to find her. (This is an adaptation of Chrétien's Conte du Graal with a couple of alterations: Lancelot is naturally no longer the "Fair Unknown", the nameless knight; and the lovers passion is no longer a celebration of courtly love, but burdened with guilt). "Lancelot's mission is accomplished.

The knights of the Round Table are regularly on the road, often just to find each other. Lancelot roams the country. Once again he becomes Morgan's prisoner and this time he is locked up for more than two years. To kill the time he paints murals, in which he depicts his love story with Guinevere. One day he sees a rose in the garden which is more beautiful than all the other roses and therefore reminds him of his lady and gives him the strength to break the bars of his prison and escape. He is just in time to join the expedition to Europe that king Arthur undertakes to beat the Romans."

La Queste del Saint Graal:
"During the feast of Whitsun Galahad comes to the court, sits in the Perilous Seat and proves he will be the best knight of all times by drawing a sword from a stone. That night the Holy Grail appears before the court, to disappear as quickly as it came. Gawain swears to reveal the secret of the Grail and the all the knights of the Round Table follow his example.

Soon it becomes clear that the Grail is not their destiny. The knights wander through the country, but the only adventures they have, are duels with each other, because they do not recognise each other before it is too late.

Lancelot comes close to the Grail, but he is not the one because of his adulterous sins. Only Perceval, Bors and Galahad are admitted to the Grail service for which Christ appears. In the end Galahad is the only one who is initiated in the secrets of the Holy Grail. He dies in ecstasy. Bors is the only one to return and tell the tale, because Perceval dies as well."

La Mort le Roi Artu:
"At court Lancelot and Guinevere are subject to a lot of gossip. Arthur ignores the accusations until Morgan shows him the murals Lancelot made during his imprisonment. Guinevere is convicted to burn at the stake, but is saved just in time by Lancelot. In the process he kills Gawain's three brothers.

Arthur's army besieges Lancelot at his castle, but when they are facing each other directly Lancelot refuses to defend himself. Arthur is touched. After months of war the pope acts as a mediator and both sides agree to a compromise. Guinevere is restored to favour and Lancelot withdraws himself to France.

Gawain however is still after revenge for the death of his brothers and Arthur leads his troops to France. Lancelot defeats Gawain in a duel, and the latter will eventually die from his wounds.

Meanwhile in Britain Mordred (at the end of Lancelot Propre it turned out that he was not Gawain's youngest brother but the child of Arthur and his halfsister Morgan) has pronounced himself king and besieges Guinevere, who has fled to London.

The armies of Arthur and Mordred slaughter each other at Salisbury. Arthur kills Mordred but is mortally wounded himself. He orders Excalibur to be thrown into the lake. A hand rises up from the water to receive the sword. Morgan arrives by ship to take Arthur to Avalon.
Lancelot avenges Arthur on Mordred's sons. As a recluse Lancelot finally finds himself at peace with God."
 

TheVulgate Cycle would be one of the sources for Malory's Morte Dartur.