- "And what do knights swear to do? Protect the weak and uphold the good."
- ―Margaery Tyrell
Knights follow a religiously influenced code of behavior and honor called "chivalry". This code states that knights must defend the weak and the innocent, must protect women and children, must fight fairly and honorably, and obey their lieges. How closely a knight follows this code varies immensely from individual to individual.
Pursuing a knighthood is one of the few ways for a member of the smallfolk to achieve rank and standing amongst the nobility. However, such a task usually involves the expenditure of significant sums of money on armor and weaponry which puts it out of the reach of most commoners. The rank of knighthood is not hereditary, and thus a knight's sons must go through the whole process of becoming knights themselves. Of course, a commoner who has been knighted will have greater opportunity to gain the wealth needed to put his sons through training as knights.
In peacetime, knights prove their martial valor through training and contests of skill known as tournaments.
Knights have to be devout followers of the Faith of the Seven. As such, non-followers of the Faith, such as most of the inhabitants of the North (who follow the Old Gods of the Forest instead) and the Iron Islands (who follow a deity called the Drowned God) cannot become knights. Because it is tied to the Faith of the Seven, knighthood does not exist in other cultures outside of the Seven Kingdoms, either among the wildlings Beyond the Wall, or across the Narrow Sea in other continents such as Essos (though of course, a knight from the Seven Kingdoms may travel to the Free Cities). Sometimes, however, a soldier who does not follow the Faith of the Seven may nonetheless be rewarded for exemplary service with the title of knighthood by a lord who does worship the Seven, i.e. Ser Rodrik Cassel of the North.
In the books
In the A Song of Ice and Fire novels, knighthood is an institution that came with the Andals when they invaded Westeros some six thousand years ago. Knights wore armor (derived from iron) and rode horses into battle, using massed-formation charges and lances to shatter enemy armies. The devastating effectiveness of this tactic permitted the Andals to conquer most of Westeros. This tactic was later adopted by others, so the cavalry of the North uses much the same weapons, armor and tactics as knights, but are not called knights due to their devotion to another god. In practice, there is little difference between knights and Northern heavy cavalry.
There are several types of knight:
- Hedge knights are typically commoners who have risen to knighthood. They have no fixed abode and wander the Seven Kingdoms looking for a cause to fight for. They are called "hedge" knights because it is said that they are so poor that they just sleep under hedges by the side of the road as they wander from one job to the next.
- Sworn swords are knights sworn to a particular lord. Sometimes this is permanent, but mainly it is temporary, with hedge knights joining a lord for a particular purpose and then being released from his service afterwards.
- Landed knights are knights who have been rewarded for their service by a lord with land, typically a smallholding, large farm or small manor with servants. They form the minor nobility of the Seven Kingdoms. Successful landed knights who expand their holdings or continue to perform exemplary service for their liege may be raised to the rank of "Lord" in time, leading a major noble House.
Most knights pass through three stages to achieve the rank. They start as pages, young boys who perform menial tasks for their lieges. Pages are not expected to fight in battle, but some do regardless. They are given lessons in riding and weapons in return. Upon reaching adolescence, pages become squires. Their training intensifies and they are taught the full comportment and responsibilities of knighthood. Squires are expected to fight in battle and carry themselves as knights at all times, even though they have not achieved the rank yet. They finally become full knights after they have proven themselves. Any knight can make another knight.
Thus the full course of steps for a prospective knight is: Page-->Squire-->Hedge Knight-->Sworn Sword-->Landed Knight. A man does not necessarily have to go through the first two steps to become a knight: if a commoner has significantly distinguished himself in combat, a knight may choose to elevate him to knighthood. Even a sellsword that has fought valiantly in combat may be rewarded by being dubbed a knight, though this is uncommon.
Further, a soldier who is rewarded by a lord for valorous service by being dubbed a knight might instantly be taken on by that lord as a sworn sword within his own household, skipping the hedge knight step. Further, while rare, it is not unheard of for a lord to reward a common soldier not only by dubbing him a knight, but by at the same time giving him lands, instantly elevating him from a simple soldier to a "landed knight" and member of the minor nobility, skipping the steps of "hedge knight" or "sworn sword" entirely. This was the case with Ser Davos Seaworth, who was a common low-born smuggler, but performed such valorous service running the blockade around Storm's End to bring food to the besieged castle's starving garrison, that Stannis Baratheon rewarded him by not only knighting him but giving him lands to rule.
Becoming a knight requires the applicant to swear an oath of allegiance and fealty to the Seven and to stand vigil in a sept for a night (these tasks need not be performed consecutively: it is not uncommon in times of war for a newly-made knight to not stand his vigil for weeks or months).
There is no formal bar against women becoming knights, only that it is simply not done. There is no "official" rule against women becoming knights, because it makes as much sense in their culture as making an official rule forbidding pigs to fly: it is absurd and simply impossible for a woman to be a knight. While rare, female warriors have served as pages and squires.
"Ser" is not a typo: the title for knights within the fictional universe of the A Song of Ice and Fire book series is spelled "S-e-r" with an "e", not as "sir" with an "i" as in real life. This is just a quirk of their culture. According to the TV series official pronunciation guide developed for the cast and crew, "Ser" is pronounced "SAIR". Actors usually say it very fast or slur it so it sounds very similar to the standard "sir", but this is not the case. That is, actor Sean Bean isn't saying "sir" with a Received Pronunciation accent so it sounds like "SAIR", the correct pronunciation of "ser" actually is "SAIR". On the WinterIsComing.com fansite, writer Bryan Cogman clarified that some pronunciations would differ due to the accents and languages of the speaker, "Ser" in particular.