An ichimon is a family-style grouping of sumo stables (heya, also pronounced -beya in compounds) that trace back to a shared root. There are five main ichimon: Dewanoumi, Nishonoseki, Tokitsukaze, Isegahama, and Takasago. Each wrestler belongs to one heya, and each heya belongs to one ichimon. The grouping began as a cooperative for the touring circuit and became the structure through which stables produce the association’s directors. This guide explains what each ichimon is and how the modern lineage map took shape.
Key takeaways
- The five main ichimon are Dewanoumi, Nishonoseki, Tokitsukaze, Isegahama, and Takasago.
- An ichimon is a lineage of stables linked by a main house (honke) and its branch houses (bunke).
- It started as a cooperative for the touring circuit (jungyo) and now produces the directors who run the Japan Sumo Association.
- The board (rijikai) has 10 directors (riji), headed by a chairman (rijicho); the current election structure dates to the 1968 reform.
- The number of elders an ichimon holds shapes how many directors it can send to the board.
What an ichimon is
Professional sumo is organized into heya, the training stables where wrestlers live, practice, and are coached by a stablemaster who holds an elder name. Stables do not exist in isolation. Each one belongs to a larger grouping called an ichimon, which works as an extended family of stables that share a common origin.
The relationship at the heart of an ichimon is the one between a main house (honke) and its branch houses (bunke). A senior stable gives rise to new stables when its wrestlers retire and set up on their own, and those new stables stay linked to the parent within the same ichimon. According to the writer Michihiro Taguchi, when he was first becoming aware of sumo, tournament matchups themselves were arranged by lineage. Bouts were drawn up along these family lines rather than freely across the whole banzuke.
The five ichimon
Sumo recognizes five main ichimon. The number of elders (toshiyori) inside each lineage matters, because an ichimon with more elders can send more directors to the board. Taguchi records the following counts as of 2022.
| Ichimon (lineage) | Elders (toshiyori), 2022 |
|---|---|
| Dewanoumi | 36 |
| Nishonoseki | 30 |
| Tokitsukaze | 16 |
| Isegahama | 12 |
| Takasago | 11 |
Those numbers connect directly to power inside the sport. The board (rijikai) of the Japan Sumo Association has 10 directors (riji), headed by a chairman (rijicho), and the directors are drawn from the elders. So a lineage that holds more elder stock (toshiyori-kabu) carries more weight when the board is chosen. The current structure of director elections was set by the 1968 organizational reform. Before that, above the directors sat four to five managing officers (torishimari), including the chairman.
How stables group into lineages
The lineages grow by branching. An ichimon began as something like a cooperative union for the touring circuit (jungyo), which ran on an independent-accounting basis, and it later evolved into a joint organization that produces directors. Viewed from the stables’ actual roots, the present-day map has become tangled. Decades of branchings, denied or granted independences, and the occasional break with a parent stable mean the family tree no longer maps cleanly onto a single ancestral line.
The exception proves the pattern. A stable without a lineage behind it had to fight alone. Ise-no-umi-beya lacked the honke-bunke relationship, so its wrestler Kashiwado was matched against Toyoyama of Tokitsukaze-beya in what Taguchi calls a lone struggle (kogun funto), because no family network shaped such pairings.
The Dewanoumi ichimon
The Dewanoumi lineage is the largest, and it traces to Dewanoumi-beya, built up within a single generation by the Meiji-era wrestler Hitachiyama, revered as a kakusei (“sumo sage”). From that root, new stables split off as senior figures retired and were granted, or in some cases denied, permission to go independent.
Tochigiyama received permission to go independent before the no-branching rule existed, and he founded Kasugano-beya. The rule that branch independence was not permitted (bunke dokuritsu o yurusazu) began under the Dewanoumi stablemaster formerly known as Ryogoku, whose earlier ring name was Kuniiwa. Where that rule held, a stable could not spin off. Where it later broke down, the lineage spread further.
The rule effectively ended under the Dewanoumi stablemaster formerly known as Sadanoyama. After it lapsed, Mienoumi founded Musashigawa-beya, today’s Fujishima-beya, and the former Ryogoku, whose earlier ring name was Kobayashiyama, founded Nakadachi-beya, today’s Sakaigawa-beya. A separate split came through an expulsion-style independence (hamon dokuritsu): Chiyonoyama, having lost the path to succeed Dewanoumi after Sadanoyama became the heir, broke away with Kitanofuji and others. That line leads to today’s Kokonoe-beya and Hakkaku-beya.
The Nishonoseki ichimon
The Nishonoseki lineage spread because the disciple Tamanoumi set the policy of permitting independence to anyone willing to train disciples. Branches grew to Hanakago, Sadogatake, Katonami, and Taiho.
Its main house, by contrast, became extinct. The Nishonoseki name passed from the 2nd Kaizan to Tamanishiki, then Tamanoumi, Saganohana, Tokachiiwa, and Kongo, and it ended in Kongo’s generation. That left an ichimon with no main house (honke naki ichimon).
The Takasago ichimon today
The Takasago lineage had shrunk by 2022. It consisted of Nishikido-beya (Mitoryu) plus the Dewanoumi-rooted Kokonoe-beya and its branch Hakkaku-beya. Hakkaku, the former Hokutoumi, served as chairman of the association during that period.
Frequently Asked Questions
What are the five sumo ichimon?
The five main ichimon are Dewanoumi, Nishonoseki, Tokitsukaze, Isegahama, and Takasago. Each is a lineage of stables that share a common origin, and every heya belongs to one of them.
What is the difference between a heya and an ichimon?
A heya (or -beya in compound names) is a single sumo stable: the household where wrestlers train and live under one stablemaster. An ichimon is the larger family of stables that share a common origin. Every heya belongs to exactly one ichimon, and a heya typically traces its descent to a main house (honke) within that ichimon.
What does an ichimon actually do?
It began as a cooperative for the touring circuit (jungyo), run on an independent-accounting basis, that pooled the stables of a lineage for shared logistics. Over time its weight shifted toward governance. The ichimon became the grouping through which member stables produce directors for the Japan Sumo Association, whose board holds 10 directors headed by a chairman.
What is the Dewanoumi ichimon?
Dewanoumi is the largest ichimon, with 36 elders as of 2022. It traces to Dewanoumi-beya, built in a single generation by the Meiji-era wrestler Hitachiyama. Its house rule against branch independence (bunke dokuritsu o yurusazu) once limited new stables, and once it lapsed the lineage spread to houses such as today’s Fujishima-beya, Sakaigawa-beya, Kokonoe-beya, and Hakkaku-beya.
Why does the Nishonoseki ichimon have no main house?
The Nishonoseki name passed through a chain of holders, from the 2nd Kaizan down to Kongo, and ended in Kongo’s generation. That left a lineage with no main house, a honke naki ichimon, even though its branches such as Hanakago, Sadogatake, Katonami, and Taiho continued.
Why does the modern map of ichimon look so complicated?
Because lineages grow by branching, and the rules for branching were not uniform. Some parent stables forbade their wrestlers from going independent, while others allowed it; some breakaways happened on good terms and others through expulsion. After many generations of these splits and successions, the family tree of stables no longer lines up with a single ancestral chain.
Based on Japanese explainers by Michihiro Taguchi on sumo lineages (ichimon) and the relationships between stables. Lineage-specific details, elder counts, and governance figures above reflect Taguchi’s account.
