were armed military leagues that formed in several regions of Japan in the 15thâÂÂ16th centuries, composed entirely of members of the Jà Âdo Shinshà « sect of Buddhism. In the early phases, these ikki leagues opposed the rule of local shugo (governors) or daimyà  (lords), but over time as their power consolidated and grew, they courted alliances with powerful figures in the waning Ashikaga shogunate until they were crushed by Oda Nobunaga in the 1580s.
Ikkà Â-ikki mainly consisted of priests, peasants, merchants, and jizamurai (local military rulers) who followed the sect, but they sometimes associated with non-followers. The ikkà Â-ikki included organisations of sà Âhei "monk warriors", similar to the lay or semi-lay military orders of medieval Christianity. They were at first only slightly organized. However, during the reforms of the monshu Jitsunyo and, later, under his grandson Shà Ânyo, the temple network enabled more efficient and effective troop mobilization when needed. The relationship between Hongan-ji and its monshu was complicated: some monshu, such as Rennyo, condemned the violence, others, such as Shà Ânyo and Kennyo, channelled it to further political aims. With improvements in matchlocks firearms (teppo) at the time, called Tanegashima, ikkà Â-ikki could suddenly rise as a menacing force, posing a credible threat to the government. A peasant or merchant could transform himself into a capable mobile cannoneer in mere days.
An in medieval Japan could be formed by any group that had a single goal in mind and vowed to stay together to achieve it. Carol Tsang lists two general categories of ikki:
By contrast, ikkà Â-ikki defies easy categorization. The term refers to the exclusive emphasis of the Jà Âdo Shinshà « of striving for rebirth in the Pure Land of Amitabha. For this reason, Jà Âdo Shinshà « was often pejoratively called the ikkà Â-shà « or "'Facing one direction' sect". In any case, in contrast to other ikki, ikkà Â-ikki were defined not by political, familial, or economic association, but by a sense of community through their association with Jà Âdo Shinshà «.
Adherents of Nichiren Buddhism formed hokke-ikki ("Lotus (Sutra) leagues") to oppose both Jà Âdo Shinshà «, which they religiously opposed, and to fight ikkà Â-ikki, as well as for mutual aid and defence.
The first recorded instances of an ikki date as far back as the 14th century in Bingo Province. However, with the waning years of the Muromachi period and the subsequent Sengoku period was characterized by weakening central power, and frequent conflicts between rival forces, the number of ikki proliferated. The first large-scale peasant uprising occurred in 1428 when a tokusei-ikki from à Âmi and Yamashiro provinces marched on Kyoto, the capital.
According to George Sansom, The Shirahata-ikki, "White Flag League", and Mikazuki-ikki, "Crescent League", are examples of the many ikki who rose against the Ashikaga shogunate. An uprising involving an entire province was called a kuni-ikki. Uprisings took place in 1351, 1353, 1369, 1377, 1384âÂÂ1386, and 1366âÂÂ1369.
The risings in the 15th century, tsuchi-ikki or do-ikki, were better organized, and the peasants appear to have played a more prominent part. At the conclusion of the à Ânin War, in 1477, "many of the members of the numerous ikki" occupied the monasteries and shrines, and "would ring the warning bells day and night, hoping to terrify the rich citizens", according to Sansom.
Ikkà Â-ikki were initially disparate and disorganized followers of Rennyo's teachings. His missionary work and his appointment as abbot of Kyoto's Hongan-ji in 1457 enabled him to "express in words and deeds" his unorthodox views. The first instances of the Ikkà Â-ikki as a defensive league were formed in à Âmi Province to defend against the threats and violence from the Tendai-adherent sà Âhei armies of Enryaku-ji. The eighth monshu, Rennyo, proselytized in this area, and the growing influence threatened Enryaku-ji's interests there. Despite some efforts at a peaceful negotiation, including payments to cover any tax revenue shortfalls, the sà Âhei of Enryaku-ji attacked local communities at Katata in 1465. Jà Âdo Shinshà « communities attempted to fortify their temples and villages, but failed to withstand the assaults by Enryaku-ji. The attacks resumed in 1468, resulting in the destruction of Hongan-ji, and by 1471 Rennyo and his family fled to the village of Yoshizaki in Echizen Province.
A new temple community was established at Yoshizaki-gobà  in 1471. It was here that Rennyo began to attract a significant following through extensive letter writing, clarifying orthodox Jà Âdo Shinshà « doctrine, and refuting the teachings of rival subjects, in particular the Takada-shà «. The village of Yoshizaki grew to a large, fortified community by 1473, and a network of temples across grew to accommodate increasing numbers of followers. Rennyo assigned family members to head new temples, or to manage existing temples, further strengthening the network. Disruptions by local Ikkà Â-ikki leagues forced Rennyo to draft a series of rules for proper conduct in 1475, which Jà Âdo Shinshà « adherents were expected to follow, with limited effect.
An ongoing dispute between members local governorships forced the Hongan-ji sect to become involved in 1473 leading to a series of skirmishes and alliances in the 1470s and 1480s. By 1486, the conflict culminated in the Kaga Rebellion, which overthrew the governor of Kaga Province and established self-rule as the Kaga ikki; this represented the first time in Japanese history that a group of commoners ruled a province.
Rennyo, who was in a separate province at the time, was compelled by the authorities to admonish ikkà Â-ikki rebellions, to little effect, and stepped down as the Patriarch in 1489, before dying of illness in 1499. After stepping down, his second son, Jitsunyo, became the 9th monshu, and initially followed a conservative, cautious administration at first.
A complex dynastic dispute within the Ashikaga shogunate in 1493, with the forced deposition of Ashikaga Yoshitane by his former deputy shogun, Hosokawa Masamoto, led to a conflict between Yoshitane's faction led by the Hatakeyama clan and their opponents, the Hosokawa clan. Masamoto forcefully enlisted military aid from the 9th monshu, Jitsunyo, in particular to help with a stalled assault on Hatakeyama Yoshihide at Konda castle in late 1505. According to the account, Jitsunyo initially fled from Masamoto's approach, and retreated to à Âtsu, but Masamoto pursued him, reportedly cornering him until he relented. Jitsunyo had enjoyed the patronage of Masamoto, including protection from prosecution from the 1488 rebellions, but initially refused, citing his role as a priest and not a warrior. Eventually, Jitsunyo relented.
While most Hongan-ji temples heeded the call to arms, some factions in Settsu and Kawachi provinces supported Yoshitane's faction, and refused to fight under the Hongan-ji banner. Nonetheless, in 1506, ikkà Â-ikki armies helped defeat Konda castle, defeating Asakura Norikage in the of 1506, and triggering further uprisings in neighboring Etchà «, Echizen, and Noto provinces, followed later by Mikawa Province. By 1507, Masamoto had been assassinated and fighting amongst Hosokawa successors led to a stalemate.
During this time, Jitsunyo reformed the hierarchy of the Hongan-ji and its network of temples into either temples staffed by family members, or temples with more autonomy, but subordinate to Hongan-ji. This increased centralization was intended to improve administration, but it also enabled ikkà Â-ikki forces to be more effectively mobilized. In addition to these reforms, the letters of Rennyo were collected and a subset were selected as a core party of Jà Âdo Shinshà « doctrine, known as the or alternatively leading to increased uniformity.
Following Jitsunyo's death in 1525, Jà Âdo Shinshà « temples in the provinces increasingly formed into : fortified temple communities that did not permit military officials to enter, while also managing their own tax collection. Meanwhile, ikkà Â-ikki also established a fortress complex at Ishiyama Hongan-ji, just outside Osaka in 1496, and in Nagashima, on the borders of Owari and Ise Provinces and in a series of temples in Mikawa Province as well.
By the 1530s the Hongan-ji was directly involved in a series of conflicts, starting with the conflict in Kaga Province, pitting the 10th monshu, Shà Ânyo, against rebellious temples, followed soon after by military assistance to Hosokawa Harumoto in the of 1532âÂÂ1536. The Ikko-ikki defeated Nagao Tamekage in the 1536 Battle of Sendanno. By July 17th of that year, local Ikko-ikki forces marched into Nara and sacked it, looting Kasuga Shrine. Unlike his predecessors Shà Ânyo did not hesitate to mobilize forces, or discipline temples that were non-compliant.
The Ikko-ikki also fought Asakura Norikage again in the 1555 Battle of Daishoji-omote.
Towards the end of the 16th century, their growing numbers and strength caught the attention and concern of the great samurai leaders of the time. Tokugawa Ieyasu worried that the ikkà Â-ikki of Mikawa Province would rise up and seize the province. In 1564, his forces, with the help of Jà Âdo-shà « forces, defeated the Mikawa-ikki in the Battle of Azukizaka.
By this point, Ishiyama Hongan-ji and other strongholds of the ikkà Â-ikki lay across major trade routes and occupied the same areas that Nobunaga saw as his primary territorial objectives. Nearly every road to the capital from this western part of the country was controlled by ikkà Â-ikki or their allies, and their populist roots gave them significant economic power as well. Nobunaga in particular sought the destruction of the ikkà Â-ikki for these reasons, and because they allied themselves with nearly every one of his major enemies or rivals. Ashikaga Yoshiaki was once strongly supported in his claim to become Shà Âgun by Nobunaga, but turned to the ikkà Â-ikki when their relationship soured. The ikkà Â-ikki also had powerful allies in the Mà Âri, Azai, and Asakura clans. In the Asakura stronghold of Echizen Province (now Fukui prefecture, Nobunaga ordered his generals to kill the people in Ajimano (a village now part of Echizen, Fukui) in August 1575, as noted in The Chronicle of Lord Nobunaga. Ishiyama Hongan-ji was besieged several times by the forces of Oda Nobunaga in the Ishiyama Hongan-ji War, as was the Sieges of Nagashima. After several failed attempts at seizing each emplacement, Oda successfully defeated Nagashima by 1574 after a four-year siege, and Ishiyama Hongan-ji in 1580 after an 11-year siege.
The majority of the Hongan-ji forces, including the 11th monshu, Kà Âsa, Shà Ânyo's son, submitted to Nobunaga's authority, relinquishing much of their independence in the process, though a few holdouts resisted as late as 1585.
In the 1580s, the last of the ikkà Â-ikki courted Toyotomi Hideyoshi, and fought alongside his forces against warrior monks and priests of other sects.
The Ikkà Â-ikki bands of the 16th century, owing largely to their origins as countryside mobs, employed a wide range of armour and armament. Many wore the more traditional priest robes, with varying degrees and types of armour. Some wore various types of helmets, while others opted for a peasant's straw hat and cloak. Naginata remained very common, along with a variety of swords and daggers, and a limited number of Tanegashima firearms. A very common item wielded by the Ikkà Â-ikki priest-warriors was a banner bearing a Buddhist slogan. Some of the more common slogans included the chant Namu Amida Butsu () and "He who advances is sure of salvation, but he who retreats will go to hell".
Jà Âdo Shinshà « was persecuted in response to the Ikkà Â-ikki, which caused the formation of kakure nenbutsu secret societies.