Ikkoshu is a Buddhist sect founded by Ikko Shunsho, a Jodoshu sect monk during the Kamakura period. The sect was forcibly integrated into the Jishu sect and renamed 'the Ikko school of the Jishu sect' by the Edo bakufu (Japanese feudal government headed by a shogun).
A name used by others to indicate the Jodo Shinshu sect (the True Pure Land Sect of Buddhism), especially the Hongan-ji school.
From the viewpoint of Buddhist history, the first definition is considered the only correct definition of 'Ikkoshu'; in practice, however, as with the impression of the Ikko ikki uprising during the Sengoku period (period of warring states) and forcible integration (the ban on using the name 'Ikkoshu') by the Edo bakufu, as in the first definition, and the forcible renaming of the Jodo Shinshu sect (forcing the Jodo Shinshu sect to use the name 'Ikkoshu') by the Edo bakufu, as in the second definition, the second definition is now generally adopted.
Ikkoshu' of Ikko Shunsho
The sect founded by the monk Ikko Shunsho (ca.1239 - ca.1287) during the Kamakura period is sometimes called 'Ikkoshu.'
Ikko Shunsho, a descendant of the Kusano clan in Chikugo Province, was originally a monk of the Chinzei school of the Jodoshu sect; according to another opinion, he was a monk of the Nishiyama Jodoshu sect.
He later made pilgrimages around Japan, during which he practiced a Buddhist invocation accompanied by 'Odorinenbutsu' and 'Tendonenbutsu' dances, and founded a seminary.
Renge-ji Temple was subsequently made the head temple of Ikkoshu, and its teachings were propagated in Tohoku, Northern Kanto, Owari, and Omi by building branch temples in the areas, forming an independent Buddhist sect. In the "Nomori no Kagami," which was written at the end of the Kamakura period, it is recorded that this sect was called Ikkoshu, and was a completely different sect from the later Jodo Shinshu sect.
(An 'Ikkoshu' appeared in the "Tengu-zoshi," but this indicated the people of another sect headed by Ippen. [See 'Ikko Shunsho'])
However, since Ikko Shunsho propagated his teachings and raised funds for temples by performing pilgrimages and 'Odorinenbutsu,' just as Ippen of the Jishu sect did during the same period, people confused the Ikkoshu and Jishu sects.
Both Ikko Shunsho and Ippen established their original doctrines under the influence of the Jodoshu sect, but their sects were completely independent from each other.
It is considered that the teachings of Ikko Shunsho were the same as those of Ippen in that both performed Odorinenbutsu, but different in that Ikko Shunsho did not put any particular religious meaning in the Buddhist invocation in his Odorinenbutsu.
As time passed, however, the teachings of Ikko Shunsho became mixed up with the teachings of Odorinenbutsu which Ippen had established, and these teachings became further confused with the Jodo Shinshu sect founded by Shinran.
This tendency was particularly visible in the Hokuriku region, where the doctrine of Ikko Shunsho was propagated in the early period.
When Hongan-ji Temple was destroyed by warrior monks from the Saito area of Enryaku-ji Temple, and Rennyo, the eighth head of the Hongan-ji school of the Jodo Shinshu sect, sought to find his way into the Hokuriku region, Rennyo aimed his propagation at the monks and followers who were based in the Jodo teachings under the influence of Ikko Shunsho and Ippen, collectively calling them '一向衆' Ikkoshu, meaning 'the people of Ikkoshu sect', instead of '一向宗' Ikkoshu, the name for Ikko Shunsho's sect.
Hongan-ji Temple and Rennyo's mission succeeded in the Hokuriku region thanks to the existence of the 'people of Ikkoshu sect,' whose religious concept was similar to that of Hongan-ji and Rennyo; on the other hand, though, Rennyo worried that the teachings of Shinran might be distorted by those people.
Worse still, another set of people whom other sects called 'Ikkoshu sect' for a different reason (discussed later) deepened Rennyo's worries.
In 1473, Rennyo wrote in the "Jogai Ofumi," a collection of letters, as follows:
It is called Ikkoshu, indicating the Jishu people, meaning Ippen and Ikko Shunsho.'
It originated in the seminary in Banba, Goshu.'
Here he stated that the Ikkoshu sect was a sect founded by Ikko Shunsho and that any Hongan-ji Temple believers who used the name of the Ikkoshu sect would be expelled, although he confused the sects of Ippen and Ikko Shunsho.
However, during the Edo period, the Edo bakufu attempted to introduce the strict head-branch system into all the Buddhist temples; for that reason, the bakufu denied Ikkoshu's independence as a sect, integrated it with the Jishu sect, founded by Ippen, with Shojoko-ji Temple as its head temple (because the Ikkoshu also practiced Odorinenbutsu as the Jishu sect did), and thereafter prohibited the people from using the name 'Ikkoshu.'
Although the Ikko school (the former Ikkoshu sect followers) naturally tried gain independence from the Jishu sect over and over again, they always failed.
It was in 1943, during the Showa period, that most temples were separated from the Jishu sect and returned to the Jodoshu sect, the parent organization of Ikko Shunsho.
Ikkoshu' of the Jodo Shinshu sect
Ikko' literally means 'devotedly' or 'earnestly,' indicating the devotion of oneself to one thing.
Since it was described 'Ikko Sennen Muryo Jubutsu' (一向専念無量寿仏) in the sutra "Muryoju-kyo Bussetsu Muryoju-kyo" (無量寿経仏説無量寿経), '一向' Ikko was understood as chanting of the Amitabha's name, from which '一向宗' became a designation used by other sects to refer to the Jodo Shinshu sect founded by Shinran.
Another opinion states that it was used by the Jodoshu sect itself, who hated the name 'the Jodo Shinshu sect.'
Therefore, it was neither a correct designation from the viewpoint of the Jodo Shinshu sect, nor a desirable name, since it was confused with the 'Ikkoshu sect' founded by Ikko Shunsho.
However, during the middle ages, both of the sects which had branched from the Jodokyo and featured the chanting of the same Buddhist invocation were mixed up, and both were further confused with the Jishu sect.
As mentioned above, Rennyo stated that 'If people of other sects confuse us with another sect and call us Ikkoshu, that cannot be helped, but the people of the Jodo Shinshu sect should not call themselves Ikkoshu,' and even said that he would expel those who did not obey the order; conversely, this means that even members of the Jodo Shinshu sect called themselves Ikkoshu in those days.
Sect name controversy
The Edo bakufu (the family of the Tokugawa shogun, which controlled the country) were followers of the Jodoshu sect; the family had a hard time during the Ikko ikki uprising in Mikawa, and continued using 'the Ikkoshu sect' as the formal name.
However, in 1774, a sense of urgency over the matter grew in both Higashi (East) Hongan-ji and Nishi (West) Hongan-ji Temples, and they cooperated in the submission of a proposal to the bakufu stating that only 'the Jodo Shinshu sect' (written as 浄土真宗) should be used as their formal name; this was seconded by Jodo Shinshu schools other than the Hongan-ji school, such as the Bukko-ji and Takada schools.
Tadayori MATSUDAIRA, the commissioner of temples and shrines, was perplexed and asked Kanei-ji Temple (the Tandaishu sect) and Zojo-ji Temple (the Jodoshu sect), family temples belonging to the Tokugawa shogun's family, for their opinions about the proposal.
Kanei-ji Temple practically approved the proposal, saying that since it was another sect's matter, they entrusted it to the other sect, while Zojo-ji Temple was infuriated.
Zojo-ji Temple answered that only the Jodoshu sect, which was descended directly from the founder Honen, was the real '真' Jodo sect '浄土宗,' and that the heretical Jodo Shinshu sect should have been prohibited from using the character '真.'
The opinion of the Jodoshu sect was not groundless: Shinran, the founder of the Jodo Shinshu sect, wrote in his book "Koso Wasan" that 'his master Honen appeared from the light of enlightenment and founded the Jodo Shinshu sect, and stated his vow,' describing his master Honen as a leader of the real '真' Jodo sect '浄土宗,' expressing the master's teachings as the Jodo Shinshu '浄土真宗' and himself as the successor to Honen, and called the teachings 'the real teachings of the Jodo Shinshu sect.'
Therefore, the Jodoshu sect claimed that the believers of Shinran, who at the time stated that their teachings were different from the Jodoshu sect, were wrong to adopt 'Jodo Shinshu' as their name.
(Incidentally, half century earlier, in 1428, when Rennyo stated that they would adopt 'Jodo Shinshu' as their sect's name, Emperor Gokomatsu had Shinran raise the framed imperial calligraphy 'the first gate of the Jodo Shinshu' at the temple gate of Konkai Komyo-ji Temple.)
When Tadayori MATSUDAIRA, the commissioner of temples and shrines, resigned and was succeeded by Sukeyoshi OTA, OTA met with senior councilor Okitsugu TANUMA and decided that, in light of the distinguished contributions Zojo-ji Temple and the other Jodoshu sect temples had made to the bakufu, 'the Ikkoshu' would be the formal name of the sect which Shinran had founded.
All the branches of the Jodo Shinshu sect opposed the decision and made fierce protests to the bakufu, so it plans were made to discuss the matter again, but in reality it was merely a delaying tactic.
During the interval, Zojo-ji Temple put pressure on the Jodo Shinshu sect by distributing its opinion that only Jodoshu sect temples could use the name 'Jodo Shinshu' among all the branches of the Jodo sect, and by displaying framed calligraphy with the words 'the Jodo Shinshu' at the temple building.
The Jodo Shinshu sect was thus driven into a difficult situation, and monks from Asakusa Hongan-ji Temple eventually made a direct appeal to the senior counselor Sadanobu MATSUDAIRA, who had just passed Mt. Hakone on his way back from Kyoto to Edo in 1788.
Sadanobu MATSUDAIRA was perplexed and asked Rinnojinomiya of Kanei-ji Temple to mediate the controversy.
The following year, 1789, Rinnojinomiya suggested that Kanei-ji Temple hold the matter for '30,000 days,' after which time they should discuss the matter again, and the Jodo Shinshu sect had to obey the mediation.
This is called 'Shumeironso,' meaning controversy over the sect name.
Thereafter, the Jodo Shinshu sect consistently rejected the name 'Ikkoshu,' replacing it with 'Montoshu' and other names.
When the Meiji government was established, the government decided that it should control the Buddhist sects as part of the process of establishing Shinto as the state religion, and tried to prohibit the Jodo Shinshu sect from using any name as other than 'Ikkoshu,' including 'Jodo Shinshu' and 'Montoshu.'
The Jodo Shinshu sect pressured the Meiji government to approve their use of the name 'Jodo Shinshu,' since the Edo bakufu which had prohibited them from using the name had fallen and the promised '30,000 days' had passed.
In response, in 1872, the Meiji government answered that, taking the Jodoshu sect into account, they would not allow the Jodo Shinshu sect to use the name 'Jodo Shinshu' but would allow them to use the abbreviation 'Shinshu.'
Thereafter, the Jodo Shinshu temples that obeyed the order used 'Shinshu' as their formal name.
In contrast, the other nine schools of the Jodo Shinshu sect continue to use the name 'XXX school of the Shinshu.'