Answer:
Although Japan and Europe did not have any direct contact with one another during the medieval and early modern periods, they independently developed very similar class systems, known as feudalism. Feudalism was more than gallant knights and heroic samurai—it was a way of life of extreme inequality, poverty, and violence.
The great French historian Marc Bloch defined feudalism as:
"A subject peasantry; widespread use of the service tenement (i.e. the fief) instead of a salary...; supremacy of a class of specialized warriors; ties of obedience and protection which bind man to man...; [and] fragmentation of authority—leading inevitably to disorder."
In other words, peasants or serfs are tied to the land and work for the protection afforded by the landlord plus a portion of the harvest, rather than for money. Warriors dominate society and are bound by codes of obedience and ethics. There is no strong central government; instead, lords of smaller units of land control the warriors and peasants, but these lords owe obedience (at least in theory) to a distant and relatively weak duke, king, or emperor.
Feudalism was well established in Europe by the 800s CE but appeared in Japan only in the 1100s as the Heian period drew to a close and the Kamakura Shogunate rose to power.
European feudalism died out with the growth of stronger political states in the 16th century, but Japanese feudalism held on until the Meiji Restoration of 1868.
Feudal Japanese and European societies were built on a system of hereditary classes. The nobles were at the top, followed by warriors, with tenant farmers or serfs below. There was very little social mobility; the children of peasants became peasants, while the children of lords became lords and ladies. (One prominent exception to this rule in Japan was Toyotomi Hideyoshi, born a farmer's son, who rose to rule over the country.)
In both feudal Japan and Europe, constant warfare made warriors the most important class. Called knights in Europe and samurai in Japan, the warriors served local lords. In both cases, the warriors were bound by a code of ethics. Knights were supposed to conform to the concept of chivalry, while samurai were bound by the precepts of bushido, the "way of the warrior."
Both knights and samurai rode horses into battle, used swords, and wore armor. European armor was usually all-metal, made of chain mail or plate metal. Japanese armor included lacquered leather or metal plates with silk or metal bindings.
European knights were almost immobilized by their armor, needing help up onto their horses; from there, they would simply try to knock their opponents off their mounts. Samurai, in contrast, wore lightweight armor that allowed for quickness and maneuverability at the cost of providing much less protection.
Feudal lords in Europe built stone castles to protect themselves and their vassals in case of attack. Japanese lords known as daimyo also built castles, although Japan's castles were made of wood rather than stone.
A key distinguishing factor between the two systems was land ownership. European knights gained land from their lords as payment for their military service; they had direct control of the serfs who worked that land. In contrast, Japanese samurai did not own any land. Instead, the daimyo used a portion of their income from taxing the peasants to provide the samurai a salary, usually paid in rice.