Sento (銭湯) is a traditional Japanese public bathhouse, and the term consists of two characters: “銭” (sen), meaning “money,” and “湯” (to, or alternatively pronounced yu), meaning “hot water.” Reversing the order of the characters to “tosen,” recreates the word historically used to speak to the money charged for admission to the bath. The word “sento” remains in common use today. A more formal designation is koshuburo (公衆風呂, “public bathing place”), while ofuroya (お風呂屋, “bath shop”) may also be used. Public baths have their origins in temple baths, which were occasionally available to commoners through charity or social welfare in ancient times (Butler, 2005). However, the exact origin of paid public baths––such as sento––is not clear. The following sections will provide a comprehensive overview of the historical social functions of public baths in a general context.
A public bath is a place where people take baths in public, alongside others, whether with friends, peers, family, neighbors, or even strangers. Due to its communal nature, public baths have played a role as a social center (Clark, 1994). While its social aspect has been central since the late medieval era (1338-1600), the development of public baths historically served various social functions, not only in terms of their roles but also regarding who could access them. Particularly from the Meiji period onward until the late 1960s, most Japanese people became regular patrons of public baths, and they were arenas of social interaction and community cohesiveness (Clark, 1994, p. 67). This chapter examines the historical social functions of public baths.
2.1 Public Baths in the Ancient Period: Religious & Therapeutic Origins
Butler (2005) suggests that public baths have religious and therapeutic origins. However, its use during the ancient and early medieval eras was mainly limited to a narrow elite, and common people’s participation in bathing was typically through occasional baths offered by temples as charity of social welfare. The religious significance of bathing became especially important after the introduction of Buddhism in the sixth century. Even though water purifications were commonly part of native religious practices, Buddhism initiated a purification ritual involving bathing in large tubs or in steam baths, often in groups, as large Buddhist temples regularly featured bathhouses. For example, the Todaiji complex in Nara is believed to have had a bath where priests could purify themselves in preparation for performing religious ceremonies. Not limited to priests or clerics, emperor and courtiers also engaged in such rituals, both to prepare for officiating ceremonies or visiting temples, and as part of a rite or a conclusion to a rite. Although religious baths of the ancient and early medieval ears were primarily reserved for the elite in private settings, wealthy patrons such as local elites or royal families, sometimes funded baths for the poor as a form of charity or social welfare, providing baths in more public settings (pp. 2-5)
In contrast, hot water has long been regarded in Japan as all-encompassing natural remedy, helping to treat various ailments. This is still especially true for the water from hot springs. Butler (2005) points that therapeutic baths have origins distinct from religious baths and followed their own paths of development. Unlike the religious roots of bathing, therapeutic baths were mainly influenced by geography rather than wealth and power. For instance, natural hot springs in Arima, on the outskirt of present-day Kobe, have been popular for its medical purposes since ancient times. According to Nihon Shoki, Emperor Jomei (593-641) had excursions to Arima in 631 and 638 (pp. 5-6). As these baths became more widespread, travelers from all over Japan with medical problems often visited to soak away their aliments. On Edo-period medical texts, bathing in hot water was recommended as a cure for various ailments, including diarrhea, colds, colics, stomach aches, skin diseases, and mental issues (Wynn, 2014, p. 68). However, similar to religious bathing, therapeutic baths were also renowned as places visited by emperors and other members of the elite (Butler, 2005, p. 6).
2.2 Public Baths in the Late Medieval Era: Hygiene, Social Gatherings, & Spaces for Commoners
While baths in earlier periods were largely limited to a small elite group, the late medieval period (1338-1600) saw an expansion of bathing, with the inclusion of warriors, courtiers, clerics, and most notably common people. This shift provided an important transformation in bathing. Additionally, roles of bathing also significantly developed. Although therapeutic uses of bathing continue to today, the religious roles of bathing had been largely replaced for commercialized communal bathing practices with a greater emphasis on hygiene and social interaction since this period (Butler, 2005; Wynn 2014).
While hygiene or physical cleanliness may seem to be the obvious purpose of bating today, baths were not explicitly associate with the task of getting clean––apart from a symbolic sense–until the late medieval era. However, around this time, sources started to highlight the practical, cleaning aspect of bathing, although, social interaction in bathing was more emphasized than hygiene (Butler, 2005).
During fifteenth and sixteenth century, there was the most striking development in bathing culture that the bath became a place to gather and socialize, being a source of communal recreation or pleasure not only for the elite but also for commoners. This shift was supported by the economic growth during the late medieval era, which led to an increase in public, commercial bathhouses (Butler, 2005). As mentioned earlier, the exact origin of public baths––those charging admission fees––is not clear. However, by the year 1401, the term “sento” was being used to refer to a public bath (Zenkoku, 1973, pp. 58-59, as cited in Clark, 1994, p. 25), showing fee-based public baths started spreading by then. The proliferation of public baths is apparent in Kyoto, whereby the fifteenth century, public baths could be found without difficulty, and by the mid-sixteenth century, public baths were fixtures in many neighborhoods of the city, and some smaller cities and villages also had public baths. This was a significant cultural development, offering ready bathing opportunities for commoners––who had previously experienced only rudimentary forms of bathing–and their social superiors. Although a visit to a bathhouse could cost the equivalent of a liter of rice, as Butler (2005) suggests, it seems likely that public baths were occasionally used as a luxury by many. Abundant references to specific commercial bathhouses, as well as to “neighborhood baths,” “penny bath” (sentoburo), or rented baths, indicate that public baths were numerous and relied on the patronage of both commoners and the elite. With the establishment of public baths, bathing became an important social institution.
The popularity of communal bathing during the late medieval period marked a shift from earlier centuries. While some baths in earlier periods also provided pleasure and were often used by groups before, bathing in those contexts was not commonly described as such. Baths in ancient and early medieval times had more serious motives, such as religious rituals and therapeutic practices, rather than pleasure and communal recreation. Moreover, therapeutic and hygiene baths were typically taken individually, not in groups. However, especially after the destruction of the Onin War, the costs of heating water led proprietors to find ways to reduce fuel expenses, making hot water and steam more efficient by using them for groups rather than individuals. More importantly, there was a cultural shift that view bathing as a social activity to be done with others, whether with friends, family or neighbors. By the late medieval era, the bath became a place for communal recreation or pleasure (Butler, 2005).
2.3 Public Baths in Edo & the Modern Era: Community & Social Hubs
During the Edo period, public baths in the commercial sphere, referred to as sento, yuya, or furoya, spread widely by the end of 17th century and became an integral part of people’s life in Edo (1603-1968) (Son, 2020, p. 152; Leutner, 1985, p. 107). They were common in all urban areas to the extent that it was said, “A bathhouse in every town” or “Machi gotoni furo ari” (Clark, 1994, p. 29; Son, 2020, p. 152). While other cities had baths, they were not on such a scale. In Edo, the number of the public baths reached around 550 just before the Meiji restoration, many of which featured bathtubs large enough to accommodate twenty or more at a time. These figures were primarily driven by economic factors, as land, firewood, and water were scarce resources in a city the size of Edo, making private baths unattainable for most households (Leutner, 1985, p. 107).
These public bathhouses played an important role not only as a hygienic facility but also as a daily social meeting place for the people of Edo, where public baths were frequented for communication, recreation, and social interaction (Leutner, 1985, p. 107; Clark, 1994, p. 29). According to Robert W. Leutner’s book Shikitei Sanba and the Comic Tradition in Edo Fiction, which includes a translation and analysis of Ukiyoburo, a famous late Edo period novel set in public bathhouses (sento, yuya, furoya), the novel underscores the often disconnected dialogues of bathhouse patrons. It emphasizes the public bathhouses as a key social hub in Edo, illustrating how they served as a space for community building among people of the same social class within a particular neighborhood (as cited in Wynn, 2014, p. 69).
For example, these public bathhouses had the second floor till the early Meiji period, being exclusive for men and served as a social gathering place (Machida, 2016, p. 27). For a few coppers or more, they could have tea and light refreshments, as well as relax with conversation or a game of go or shogi (Leutner, 1985, p.107). Additionally, the public baths occasionally employed female attendants, known as yuna (literally bath girls), who would assist bathers with their clothing, wash their hair and backs, and perform sexual services (Wynn, 2014, p. 70; Clark, 1994, p. 31). Furthermore, mixed-sex bathing was common during the Edo period, as depicted in many of the sketches and paintings from this time, showing both sexes bathing together. This practice continued until the early Meiji period (Clark, 1994, p. 33-34).
Finally, in the modern era, social functions of commercial public baths, or “sento” became more distinct, and they began to proliferate in the beginning of Meiji period. The number of public baths increased by three times, largely driven by the migration of thousands of people to urban centers with the construction of factories and businesses. Housing units were constructed for factory workers, but no baths were provided. As a result, residents relied on public or factory baths (Clark, 1994, pp. 42 & 44). By the early the 20th century, most Japanese had become regular bathers at their neighborhood public baths, and baths continued to be community centers in urban areas. People bathed with their families and neighbors, exchanging news, gossip and ideas, which helped reinforce a sense of community. Commercial public baths acted as a hub for local relationships, strengthening social bonds and collective identity within neighborhoods (Clark, 1994, p. 66). Because they were both infrastructure and social spaces, children often had their first encounters with nonfamily members there. They were taught proper etiquette at the bath, including how to greet strangers and the elderly, as well as how to be aware of others and not infringe upon their space (Clark, 1994, pp. 79-80).
2.4 Bathing, Social Engagement, & the Decline of Public Baths
Overall, public baths have historically served various social functions including religious rituals, therapeutic practices, hygiene, relaxation, and, most importantly, social interaction. Especially after the late medieval era, public baths became essential social and community centers. However, the nature of the social interactions within the baths ought not to be assumed, as these interactions may be influenced by specific social contexts that facilitate engagement among bathers. Lebra (1976) explains that one of the key elements enhancing intimacy, even between strangers in any given situation, is the participants’ spontaneity––freedom from inhibition. This refers to situations where participants express themselves freely, without social constraints. In extreme cases, this leads to a form of “social nudity,” where the participants reveal their natural selves by stripping away all social masks. In a bathing setting, the act of removing all clothing correlates with the removal of social masks, encouraging bathers to engage more openly in social interaction. Moreover, as Lebra (1976) continues, intimacy behavior can thrive through the appearance of equality among participants. In a bath, all bathers share the same bath without visible makers of social status, making it easier to ignore rank distinctions. In this context, interactions among strangers can be easier to establish in public bathhouses compared to other public spaces. The term “naked association” (hadaka no tsukiai) is commonly recognized Japan to describe how co-bathing is “one of the best ways to get close together” (Clark, 1994, p. 79), showing how communal bathing experiences are seen as a way to facilitate connection and intimacy.
However, after the late 1960s, technological developments and economic affluence allowed baths to be placed in even the smallest apartment, leading to a significant decline in the number of public bathhouses and the related social activities. Public bathhouses as a center of community communication had almost disappeared (Clark, 1994, pp. 75-76). While some sento in modern times still functions as a social space among customers, as highlighted in previous literature (e.g., Sato, 2006; Miyake, 2021; Maruyama, 2023; Inoue & Yasutake, 2024), the decline of public baths suggests that an increasing number of people are losing, or have already lost, a source of community belonging, social connection, and valuable social interaction. However, parallel to the decline of public baths, a sense of belonging and connectedness has generally deteriorated in Japanese society, which will be discussed in the next chapter.