In modern Japanese usage, the term also describes a salaryman who is "between employers" or a secondary school graduate who has not yet been admitted to university.
The word rōnin literally means "wave man". That, however, is an idiomatic expression that means "vagrant" or "wandering man", someone who is without a home. The term originated in the Nara and Heian periods, when it referred to a serf who had fled or deserted his master's land. It then came to be used for a samurai who had no master. (Hence, the term "wave man" illustrating one who is socially adrift.)
According to the Bushido Shoshinshu (the Code of the Samurai), a samurai was supposed to commit seppuku (also "hara kiri" — ritual suicide) upon the loss of his master. One who chose not to honor the code was "on his own" and was meant to suffer great shame. The undesirability of rōnin status was mainly a discrimination imposed by other samurai and by daimyo, the feudal lords.
Like other samurai, rōnin wore their two swords. Rōnin used a variety of other weapons as well. Some rōnin — usually those who lacked money — would carry a bō (staff around 5 to 6 ft) or jō (smaller staff or walking stick around 3 to 5 ft) or a yumi (bow). Most weapons would reflect the ryū or martial arts school they came from, if they were students.
During the Edo period, with the shogunate's rigid class system and laws, the number of rōnin greatly increased. Confiscation of fiefs during the rule of the third Tokugawa shogun Iemitsu resulted in an especially large increase of rōnin. During previous ages, samurai were able to move between masters and even between occupations. They would also marry between classes. However, during the Edo period, samurai were restricted, and were above all forbidden to become employed by another master without their previous master's permission.
Because the former samurai could not legally take up a new trade, or because of pride were loath to do so, many rōnin looked for other ways to make a living with their swords. Those rōnin who desired steady, legal employment became mercenaries that guarded trade caravans, or bodyguards for wealthy merchants. Many other rōnin became criminals, operating as bandits and highwaymen, or joining organized crime in towns and cities. Rōnin were known to operate, or serve as hired muscle for gangs that ran gambling rings, brothels, protection rackets, and other similar activities. Many were petty thieves and muggers. The criminal segment gave the rōnin of the Edo period a persistent reputation of disgrace, with the image of thugs, bullies, cutthroats, and wandering vagrants.
n the Kamakura and Muromachi periods, when warriors held lands that they occupied, a rōnin was a warrior who had lost his lands. During these periods, as small-scale wars frequently occurred throughout Japan, the daimyo needed to augment their armies, so rōnin had opportunities to serve new masters. Also, some rōnin joined in bands, engaging in robbery and uprisings.
Especially in the Sengoku period, daimyo needed additional fighting men, and even if one's master had perished, a rōnin was able to serve a new lord. In contrast to the later Edo period, the bond between the lord and the samurai was loose, and some samurai who were dissatisfied with their treatment left their masters and sought new lords. Many warriors served a succession of masters, and some even became daimyo. As an example, Tōdō Takatora served ten lords. Additionally, the division of the population into classes had not yet taken place, so it was possible to change one's occupation from warrior to merchant or farmer, or the reverse. Saitō Dōsan was one merchant who rose through the warrior ranks to become a daimyo.
As Toyotomi Hideyoshi unified progressively larger parts of the country, daimyo found it unnecessary to recruit new soldiers. Next, the Battle of Sekigahara (AD 1600) resulted in the confiscation or reduction of the fiefs of large numbers of daimyo on the losing side; in consequence, many samurai became rōnin. As many as a hundred thousand rōnin joined forces with Toyotomi Hideyori and fought at the Siege of Osaka. In the ensuing years of peace, there was less need to maintain expensive standing armies, and many surviving rōnin turned to farming or became townspeople. A few, such as Yamada Nagamasa, sought adventure overseas as mercenaries. Still, the majority lived in poverty as rōnin. Under the third Tokugawa shogun Iemitsu, their number approached half a million.
Initially, the shogunate viewed them as dangerous, and banished them from the cities or restricted the quarters where they could live. They also prohibited serving new masters. As rōnin found themselves with fewer and fewer options, they joined in the Keian Uprising (AD 1651). This forced the shogunate to rethink its policy. It relaxed restrictions on daimyo inheritance, resulting in fewer confiscations of fiefs; and it permitted rōnin to join new masters.
Not having the status or power of employed samurai, rōnin were often disreputable and festive, and the group was a target of humiliation or satire. It was undesirable to be a rōnin, as it meant being without a stipend or farm. As an indication of the humiliation felt by samurai who became rōnin, Lord Redesdale recorded that a rōnin killed himself at the graves of the Forty-Seven Rōnin. He left a note saying that he had tried to enter the service of the daimyo of the Chōshū Domain, but was refused. Wanting to serve no other master, and hating being a rōnin, he had decided to kill himself.
On the other hand, the famous 18th-century writer Kyokutei Bakin renounced his allegiance to Matsudaira Nobunari, in whose service Bakin's samurai father had spent his life. Bakin became voluntarily a rōnin, and eventually spent his time writing books (many of them about samurai) and engaging in festivities.