The book can be read as an allegorical commentary on the civil wars and regime changes in Malory's own time. Malory was writing during the Wars of the Roses, a series of civil wars in England from 1455-1487. The wars were family squabbles as much as they were political conflicts. The House of Plantagenet had controlled the English throne throughout the Hundred Years' War with France. But after the English pulled back from France in 1453, two smaller families within the House of Plantagenet began jockeying for power. The Lancasters (eventually represented in heraldic imagery by a red rose) fought the Yorks (represented by a white rose) for decades, until the conflict was finally resolved through a marriage between the families. This resolution had not yet come when Malory wrote Le Morte d'Arthur.
In Malory's book, civil war is the great tragedy that causes Arthur's realm to fall from its former glory. Agravaine sows discord between Launcelot and Arthur by speaking up about Launcelot's affair with Guenever. Their disagreement snowballs until all the knights are picking sides. The formerly strong Round Table is now split, with one side fighting the other. Mordred exploits this new weakness to grab power for himself, and Arthur and Launcelot alike both die in the fray. The world is left without either one of these strong leaders.
The disastrous civil war in Malory's book could be taken as a cautionary tale about the civil wars Malory himself is living through. In both cases, a formerly strong regime collapses only after it starts to feel pressure from within. This interpretation is further supported by the book's treatment of Launcelot and Galahad. There is a longstanding prophecy that Launcelot will be overtaken by his son as the greatest of Arthur's knights. This is exactly what happens. Rather than fight Galahad and try to prevent him from proving himself in the quest for the Sangreal, Launcelot steps aside and lets his son outdo him. Furthermore, he takes his own failure as a sign that he should work to redeem himself. Launcelot's willingness to let a new knight become the best in the world demonstrates the kind of courage that is missing in the House of Plantagenet. This peacefully-resolved family conflict shows how everyone in the House of Plantagenet might win if they would set their pride aside and allow a peaceful regime change.
Although the book is about King Arthur and conflict among human knights, it is also a Christian allegory about the battle between good and evil. This allegory is represented through the motif of lions (representing Christ) and serpents (representing the devil). In Volume 2, Book 14, Chapter 6, Percivale sees a lion and a serpent fighting:
And then Sir Percival thought to help the lion for he was the more natural beast of the two; and therewith he drew his sword, and set his shield afore him, and there he gave the serpent such a buffet that he had a deadly wound. When the lion saw that, he made no resemblant to fight with him, but made him all the cheer that a beast might make a man.
Percivale chooses to help the lion because it seems a "more natural beast" than the snake. There is nothing inherently more natural about a lion than a snake, but there is a long tradition of iconography in which lions represent Jesus and snakes represent the Devil. In the Bible, for instance, the Devil (Lucifer) infiltrates the Garden of Eden as a snake and tempts Eve into the actions that get Adam and Eve evicted from Paradise. The Bible also refers to Jesus as a triumphant lion. This symbolism was especially common through much of the Middle Ages, when animal symbolism and beast fables were very popular. Percivale, who is questing after the Sangreal and therefore deeply invested in being a good Christian, is rewarded for choosing the lion. Percivale's assistance to the lion, and the way the lion therefore triumphs over the snake, anticipates the way Percivale will help Galahad (another Christ figure) achieve the Sangreal.
In Volume 2, Book 21, Chapter 4, an adder (a kind of snake) crawls out of a bush and bites a knight just as Arthur and Mordred are signing a treaty. The knight draws his sword, which prompts both sides to reignite the conflict:
And so they met as their pointment was, and so they were agreed and accorded thoroughly; and wine was fetched, and they drank. Right soon came an adder out of a little heath bush, and it stung a knight on the foot. And when the knight felt him stungen, he looked down and saw the adder, and then he drew his sword to slay the adder, and thought of none other harm. And when the host on both parties saw that sword drawn, then they blew beams, trumpets, and horns, and shouted grimly. And so both hosts dressed them together.
In this case, a serpent infiltrates the treaty negotiation just as the Devil once infiltrated the Garden of Eden disguised as a snake. The way the snake manages to sabotage the treaty and cause the knights to devolve into outright warfare suggests that Malory has a cynical outlook on good's ability to triumph over evil. Even though there have been many moments in the book where good won (such as when the lion beat the serpent with Percivale's help), evil is ultimately the prevailing force that leads to the death of Arthur and his realm. The lion vs. serpent motif suggests that good and evil will always be locked in battle, but that ever since Arthur's demise, the scales have been tipped toward evil.
In Volume 2, Book 17, Chapter 5, Sir Bors, Percivale, and Galahad find themselves aboard the ship called Faith. Percivale's sister tells the knights an allegorical story about four spindles that are attached to a bed on board the ship:
‘These spindles,’ said the damosel, ‘were when sinful Eve came to gather fruit, for which Adam and she were put out of paradise, she took with her the bough on which the apple hung on. Then perceived she that the branch was fair and green, and she remembered her the loss which came from the tree. Then she thought to keep the branch as long as she might. And for she had no coffer to keep it in, she put it in the earth [...].
Percivale's sister goes on to describe the creation of two white, one green, and one red spindle from this apple tree. The tree is white at first, representing Eve's maidenhood (the idea that she has never "sinned" or had sex). In this version of the biblical story, Adam asks God if he can "know" (i.e. have sex with) his wife. After Adam and Eve sleep together, leading to the birth of their son Abel, the tree turns green to represent the proliferation of life. Later, when Adam and Eve's second son, Cain, kills Abel, the tree turns red to represent blood.
As Percivale's sister reports, this tree was still standing in King Solomon's day. She goes on to tell how Solomon built the very ship they are on and, at his wife's behest, carved the spindles out of the tree. The first was red, but the tree bled out as he carved so that he eventually reached green and white wood as well. The bed, where the spindles were fastened to the canopy, was prophesied to eventually hold the "maiden" knight who would be the last of his descendants and who would be pure of heart.
The story Percivale's sister tells is tied up with Percivale, Sir Bors, and Galahad's quest. Clearly, Galahad is this "maiden" knight descended from Solomon and Adam and Eve. But there is also a subtler allegory at play as well. The Round Table creates a family dynamic much like the dynamic that causes the tree to change from white to green. Arthur and the knights of the Round Table are in a sense Adam and Eve, reveling in their brotherly love for one another and the glorious world their chivalry upholds. The love triangle among Launcelot, Guenever, and Arthur is functioning mostly to everyone's satisfaction right now, just as Adam and Eve's sexual relationship while the tree is green. But, just as Cain betrays Abel and turns the once-pure and once-vibrant tree a deep, bloody red, betrayal is on the horizon for the knights. What brings about the end of Arthur's reign and the end of this glorious time is discord among brothers. Mordred and Agravaine turn Arthur and Launcelot against one another, and the world is never the same again. While Galahad may be pure enough to sleep in the bed and to achieve the Grail, he is powerless to fully restore the family tree.
Although the book is about King Arthur and conflict among human knights, it is also a Christian allegory about the battle between good and evil. This allegory is represented through the motif of lions (representing Christ) and serpents (representing the devil). In Volume 2, Book 14, Chapter 6, Percivale sees a lion and a serpent fighting:
And then Sir Percival thought to help the lion for he was the more natural beast of the two; and therewith he drew his sword, and set his shield afore him, and there he gave the serpent such a buffet that he had a deadly wound. When the lion saw that, he made no resemblant to fight with him, but made him all the cheer that a beast might make a man.
Percivale chooses to help the lion because it seems a "more natural beast" than the snake. There is nothing inherently more natural about a lion than a snake, but there is a long tradition of iconography in which lions represent Jesus and snakes represent the Devil. In the Bible, for instance, the Devil (Lucifer) infiltrates the Garden of Eden as a snake and tempts Eve into the actions that get Adam and Eve evicted from Paradise. The Bible also refers to Jesus as a triumphant lion. This symbolism was especially common through much of the Middle Ages, when animal symbolism and beast fables were very popular. Percivale, who is questing after the Sangreal and therefore deeply invested in being a good Christian, is rewarded for choosing the lion. Percivale's assistance to the lion, and the way the lion therefore triumphs over the snake, anticipates the way Percivale will help Galahad (another Christ figure) achieve the Sangreal.
In Volume 2, Book 21, Chapter 4, an adder (a kind of snake) crawls out of a bush and bites a knight just as Arthur and Mordred are signing a treaty. The knight draws his sword, which prompts both sides to reignite the conflict:
And so they met as their pointment was, and so they were agreed and accorded thoroughly; and wine was fetched, and they drank. Right soon came an adder out of a little heath bush, and it stung a knight on the foot. And when the knight felt him stungen, he looked down and saw the adder, and then he drew his sword to slay the adder, and thought of none other harm. And when the host on both parties saw that sword drawn, then they blew beams, trumpets, and horns, and shouted grimly. And so both hosts dressed them together.
In this case, a serpent infiltrates the treaty negotiation just as the Devil once infiltrated the Garden of Eden disguised as a snake. The way the snake manages to sabotage the treaty and cause the knights to devolve into outright warfare suggests that Malory has a cynical outlook on good's ability to triumph over evil. Even though there have been many moments in the book where good won (such as when the lion beat the serpent with Percivale's help), evil is ultimately the prevailing force that leads to the death of Arthur and his realm. The lion vs. serpent motif suggests that good and evil will always be locked in battle, but that ever since Arthur's demise, the scales have been tipped toward evil.
