The Japanese feudal system began to take shape under the Kamakura bakufu, though it remained only inchoate during the Kamakura period. Warrior-landlords lived in farming villages and supervised peasant labor or themselves carried on agriculture, while the central civil aristocracy and the temples and shrines held huge public lands (kokugaryō) and private estates in various provinces and wielded power comparable to that of the bakufu. These shōen were managed by influential resident landlords who had become warriors. They were often the original developers of their districts who became officials of the provincial government and agents of the shōen. Under the Kamakura bakufu, many such individuals became gokenin and were appointed jitō in lands where the bakufu were allowed access. As leaders of a large number of villagers, these jitō labored to develop the rice fields and irrigation works in the areas under their jurisdiction, and they and other influential landlords constructed spacious homes for themselves in the villages and hamlets where they lived.

Among these landlords, some were vassals of the shogun, while others were connected to the aristocracy or the temples and shrines. The jitō owed their loyalty to the shogun, for whom they performed public services such as guard duty in Kyōto and Kamakura. In return, the shogun not only guaranteed these men security of tenure in their traditional landholdings but rewarded them with new holdings in confiscated lands—such as from the Taira or the supporters of Go-Toba. This connection between lord and vassal, on which grants of landownership or management were based, gave Japanese society a somewhat feudal character.

But these lands were by no means complete fiefs: the Kamakura bakufu did not possess large tracts of its own land that it could grant to its vassals as fiefs in return for service. Kamakura warriors could control traditional land types (shōen and kokugaryō) or be newly appointed into confiscated lands. In either case, there was a nominal absentee central proprietor—temple, shrine, or aristocratic or royal family—who maintained substantial control over the land. Thus, there was a limit on the degree to which the Kamakura warrior could exploit the land and people under his control. Conflict was endemic between central proprietor (usually a local representative of the proprietor) and jitō: the former wished to maintain as much control and income as possible while the latter was concerned with expanding his share. Since the jitō was entirely under the control of Kamakura, disputes flooded the warrior headquarters from landowners seeking to curtail jitō encroachments. Thus, the primary focus of Kamakura activity became the dispensing of justice in legal cases involving land disputes. The Kamakura bakufu gained a reputation for fairness, issuing countless orders of admonition to its vassals to follow the precedents on the land in question. By various means, however, Kamakura warriors managed to whittle away significantly the absentee control of shōen proprietors.

Conflict also was endemic between the farming population and the warriors, stemming from the efforts of the former to increase personal and economic autonomy, as well as to enlarge their holdings within the shōen or kokugaryō. There were several different statuses among the peasantry, including myōshu, prominent farmers with taxable, named fields (myōden) of significant size and long standing; small cultivators with precarious and shifting tenures; and others who paid only labor services to the proprietor or jitō. These groups, while distinct from one another, were also quite separate from transient agriculturalists present in many estates. The lowest peasant category, called genin (“low person”), was made up of people who were essentially household servants with no land rights.

The samurai, in theory, performed military service on the battlefield and during times of peace, in addition to managing agricultural holdings, engaging in hunting and training in the martial arts, and nourishing a rugged and practical character. Medieval texts speak of kyūba no michi (“the way of the bow and horse”), or yumiya toru mi no narai (“the practices of those who use the bow and arrow”), indicating that there was an emerging sense of ideal warrior behavior that grew out of this daily training and the experience of actual warfare. Pride of family name was especially valued, and loyal service to one’s overlord became the fundamental ethic. This was the origin of the more highly developed sense of a warrior code of later ages. Like his Heian predecessor, the Kamakura warrior was a mounted knight whose primary martial skill was equestrian archery. The status of women in warrior families was comparatively high; like their Heian predecessors, they were allowed to inherit a portion of the estates and even jitō posts, a practice that gradually came to be restricted.

After the middle of the Kamakura period, the farming villages in which the warriors resided underwent changes as agricultural practices advanced; other aspects of society were changing as well. Artisans were frequently attached to the proprietors of the shōen and progressively became more specialized, responding to a specific growth of consumer demand. Centers for metal casting and metalworking, paper manufacture, and other skills appeared outside the capital, in various provincial localities, for the first time. The exchange of agricultural products, manufactured goods, and other products thrived; local markets, held on three fixed days a month, became common. Copper coins from Sung China circulated in these markets, while itinerant merchants increased their activity. Bills of exchange were also used for payments to distant localities. In the large ports along the Inland Sea and Lake Biwa, specialized wholesale merchants (toimaru) appeared who, as contractors, stored, transported, and sold goods. Further, it became common for many merchants and artisans to form guilds, known as za, organized under the temples, shrines, or civil aristocrats, from whom they gained special monopoly privileges and exemptions from customs duties.

Kamakura culture: the new Buddhism and its influence

During the Kamakura period the newly arisen samurai class began to supersede the ancient civil aristocracy, which nonetheless continued to maintain the classical culture. Vigorous overseas trade expanded contacts with the continent, fostering the introduction of Zen Buddhism (in Chinese, Ch’an) and Neo-Confucianism from Sung China. Chinese influences could be seen in monochrome painting style (suiboku-ga), architecture, certain skills in pottery manufacture, and the custom of tea drinking—all of which contributed to the formation of early medieval culture and exerted an enormous influence on everyday life in Japan.

In matters of religion, the great social changes that took place between the end of the Heian period and the early Kamakura period fostered a sense of crisis and religious awakening and caused the people to demand a simple standard of faith, in place of the complicated teachings and ceremonies of the ancient Buddhism. The warriors of the farming villages, in particular, demanded a religion that would suit their personal experience. Several new Buddhist sects sprang up that eschewed difficult ascetic practices and recondite scholarship. Among these may be included the Jōdo, or Pure Land, sect mentioned earlier and its offshoot, the Shin (True) school, which sought reliance on the saving grace of Amida, and the sect established by the former Tendai priest Nichiren, which sought salvation in the Lotus Sutra. By contrast, the Zen school sought to open the way to insight by self-effort (jiriki); hence, it met with a ready response, satisfying the demands of many samurai. At the same time, scholarship and the arts were still deeply linked with the Tendai and Shingon sects of esoteric Buddhism, which was a vigorous influence even in Shintō circles. Nonetheless, the new forms of worship expanded popular participation in Buddhism tremendously.

In scholarly and literary circles, the Kyōto nobility confined themselves largely to the annotation and interpretation of the ancient classics and to the study of precedents and ceremonies. But at the beginning of the Kamakura period, a brilliant circle of waka poets around the retired emperor Go-Toba produced a new imperial selection of poems entitled the Shin kokin wakashū. The waka of this period is characterized by the term yūgen, which may be described as a mood both profound and mysterious.

Just before the Jōkyū Disturbance the Tendai monk Jien (a member of the Fujiwara family) completed his Gukanshō (“Jottings of a Fool”). This is the first work of historical philosophy in Japan to incorporate a notion of historical causality, and it provides an interpretive picture of the rise and fall of political powers from a Buddhist viewpoint. Meanwhile, as warriors began to contend and mingle with court nobles, many warrior leaders developed a love of scholarship and a delight in waka poetry. One was Hōjō Sanetoki, who collected Japanese and Chinese books and founded a famous library, the Kanazawa Bunko, in the Shōmyō Temple (at what is now Yokohama). Reflecting the rise of the warrior class, military epics became popular. The most famous is the anonymously written The Tale of the Heike (Heike monogatari), the various tales of which were first recited throughout the country by Buddhist troubadours called biwa hōshi. After the middle Kamakura period, as Buddhist pessimism grew fainter, various kinds of instruction manuals and family injunctions were composed, while collections of essays such as Yoshida Kenkō’s Essays in Idleness (Tsurezuregusa) also made their appearance. The new nationalistic fervor aroused by the successful struggle against the Mongols found expression in Kokan Shiren’s Genkō shakusho (1332), a 30-volume history of Buddhism in Japan.

In the visual arts the carving of wooden images of famous monks flourished, and, after the middle of the Kamakura period, Chinese styles of the Sung dynasty also influenced Kamakura wood carving. In painting as well as sculpture, Buddhist themes began to give way to more secular works; especially popular were picture scrolls (emakimono), which took as their themes the history of temples and shrines, the biographies of founders of religious sects, and, increasingly, military epics and the secular life of both courtiers and warriors.

Decline of Kamakura society

During the troubled state of society at the end of the Kamakura period, the gokenin faced difficult times. They had borne virtually all the expense of military service against the Mongols, but their claims for reward went largely unanswered, since no lands or other wealth were confiscated from the invaders. Thus, they were financially pressed and often in debt. At the same time, important structural changes occurred in warrior houses. First, since warriors proliferated over generations while landholdings remained constant, the practice of dividing lands among heirs gave way to single inheritance, often entirely to the eldest son. The shift from divided to single inheritance was accelerated in the post-Mongol era and became the primary means of inheritance in warrior families. Power thus became concentrated in the head of the house, to whom other family members were of necessity subordinated. Second, deputies sent out by the heads of eastern warrior families to oversee their distant landholdings often broke with the main family. They formed strong ties with other local warrior houses, perhaps even becoming vassals of a shugo. Minimally, their ties to the Kamakura regime weakened.

General economic conditions began to undermine the position of the bakufu vassals. Yet, despite the social crises among the landholders, trade was flourishing. Coins came increasingly into circulation, and the urban lifestyle began to be imitated in the provinces. But landowners were often unable to meet their expenditures from the income of their limited holdings, even if they practiced single inheritance. Therefore, they borrowed money at high rates of interest from rich moneylenders, and many were forced to surrender their holdings when unable to repay their loans. The bakufu responded with debt-cancellation edicts, which gave temporary relief but neglected the long-term problem. Consequently, the gap between rich and poor became marked among the bakufu. In particular, some shugo, who had the right to raise troops, attempted to turn resident landlords into their vassals. Thus, the vassalage structure of the Kamakura regime began to unravel, and powerful local magnates, nominally Kamakura vassals, began to challenge the authority of the Hōjō regents in the bakufu.

The Ashikaga, Sasaki, Shōni, and Shimazu families were among the most powerful among these. Buffeted by economic changes beyond its control, the bakufu began to totter, shaken also by the disputes between the Hōjō family and the rival shugo. The Adachi family was forced into revolt and defeated by the Hōjō in 1285, along with other warrior houses accused of plotting with them. Subsequently, the main Hōjō house turned increasingly inward and autocratic, further alienating other vassal houses. When the Andō family raised a revolt in Mutsu province at the end of the Kamakura period, the bakufu found it difficult to suppress, partly because of the remoteness of the site of the uprising.

In addition, regional unions of small landlords developed in the Kinai (the five home provinces centered around Kyōto). Elsewhere as well, local warriors with grievances increasingly took the law into their own hands, seizing crops or otherwise disturbing local order. Termed akutō by the authorities, they included many different elements: frustrated local warriors, pirates, aggrieved peasants, and ordinary robbers. Cultivators as well took advantage of unsettled times to rise up against jitō or shōen proprietors.

These accumulating weaknesses of the bakufu prompted a movement among the Kyōto nobility to regain political power from the military. The occasion was provided by the question of the imperial succession. In the mid-13th century two competing lines for the succession emerged—the senior line centered on the Jimyō Temple in Kyōto and the junior line centered on the Daikaku Temple on the western edge of the city. In the last half of the century, each side sought to win the support of the bakufu. In 1317 Kamakura proposed a compromise that would allow the two lines to alternate the succession. But the dispute did not cease. Finally, in 1318 Prince Takaharu of the junior line acceded to the throne as the emperor Go-Daigo.