Chivalry is a technology in Age of Empires II: The Forgotten that is unique to the Franks and can be researched at the Castle once the Imperial Age is reached. Once researched, it increases the working speed of Stables by 40%.
For a Knight which is usually created in 30 seconds, this technology, combined with Conscription (which should be researched first), reduce its creation time to 16.1 seconds.
As the vast majority of a Frankish army consists of Knights and their upgrades, Chivalry helps a lot with making a large army in a short amount of time. It should be researched if the player already has a minimum of five Stables and optimally around nine of them. With the resources it takes to research Chivalry, over five Knights can be created, but if the player economy is thriving they should research this in order to gain an edge on military production by speeding up the creation of Knights. It might also be useful if the player finds that they are being pressured and do not have the room to build extra Stables. While the Light Cavalry are not as useful as their Knights, it is worth mentioning that they do benefit from this technology.
Since Conscription is cheaper and reduces Chivalry's research time, it should be researched first.
Since the bonus applies to Stables' work rate, it also speeds up the researching of technologies at the Stable as well. Typically by the time Chivalry is researched the only remaining Stable technology left to research will be the Paladin upgrade. This is still a welcome benefit as this upgrade has a very long research time and having Chivalry and Conscription researched beforehand will significantly reduce the research time (from 170 to 91 seconds). If the player is lagging behind in other Stable technologies then Chivalry will speed those up as well.
Lords of the West
The code of chivalry that developed in medieval Europe had its roots in earlier centuries. It arose in the Carolingian Empire from the idealisation of the cavalryman—involving military bravery, individual training, and service to others—especially in Francia, among horse soldiers in Charlemagne's cavalry. The term "chivalry" derives from the Old French term chevalerie, which can be translated as "horse soldiery". Originally, the term referred only to horse-mounted men, from the French word for horse, cheval, but later it became associated with knightly ideals.
The ideals of chivalry were popularized in medieval literature, particularly the literary cycles known as the "Matter of France", relating to the legendary companions of Charlemagne and his men-at-arms, the Paladins; and the "Matter of Britain", informed by Geoffrey of Monmouth's "Historia Regum Britanniae", written in the 1130s, which popularized the legend of King Arthur and his knights of the Round Table.