Tosa Clan

During the Edo period, Tosa Province (Kochi Prefecture) was the domain of the Tozama clan. After the Battle of Sekigahara in 1600 (Keicho 5), Yamauchi Kazutoyo became the founder of the Tosa clan, and from then until the Meiji Restoration of the Domain and the Abolition of the Domains and Prefectures, the clan continued for 16 generations, including Tadayoshi, Tadatoyo, Toyomasa, Toyofusa, Toyotaka, Toyotsune, Toyonobu, Toyochika, Toyokazu, Toyoki, Toysuke, Toyoteru, Toyotetsu, Toyoatsu, Toyonobu, Toyoshige, and Toyonori. The kokudaka (rice yield) was 202,600 koku, but in reality it was 248,300 koku according to the results of the Chosokabe land survey. This was the Honda taka, and with the development of new fields, it grew to about 500,000 koku around the time of the Meiji Restoration. It is also called the Kochi Domain.

After entering the domain, Kazutoyo either suppressed or appeased the remaining Chosokabe retainers (Ichiryo Gusoku), and established a ruling system by placing his clan members and senior vassals in key locations such as Nakamura, Sukumo, Sagawa, Kubokawa, Motoyama, and Aki. He built Kochi Castle and established a castle town. The second lord, Tadayoshi, used Nonaka Kaneyama to solidify the foundations of the domain's administration. Kaneyama implemented policies such as the development of new fields, port development, industrial development, the monopoly law, and the promotion of local samurai. The domain's samurai were divided into upper samurai (elder retainers, middle retainers, horsemen, page groups, and house guards) and lower samurai (local samurai, servants, foot soldiers, and samurai servants), and class discrimination was severe. Politics in the domain was led by a Bugyoshoku (magistrate) appointed from among the elder retainers, but the actual work was done by the Shiokiyaku (councillor) appointed from the Churo and Umamawari and the various magistrates below them, while trials and police were handled by the Oometsuke who oversaw the lower-ranking positions. In addition, there were Kinju elder retainers who served as aides to the domain lord, and there were Rusuiyaku in Edo and Kyoto, and Zaiyaku in Osaka who handled liaison with the domain's home provinces. The people were controlled by the town, county and ura magistrates, and under them were Shoya (village headmen), who helped with administrative affairs in the region. A town assembly hall was set up under Kochi Castle, and town officials such as the So-Noseyori (chief elder), Shoya (village headman), Toshiyori (elder retainer), and So-Kumicho (chief leader) were in charge of town administration, but a wealthy merchant became the So-Noseyori and controlled those below the Shoya. The county magistrate supervised village officials, but each village had a village headman, a senior official, and a group leader. Small villages in the mountains had a namoto, a senior official, and a group leader, and small villages together were called "go" (towns), and each village had a chief village headman, a general elder, and a general group leader. Roadside checkpoints (barriers) were set up at the border, and the chief village headman often acted as the head clerk and the namoto as the guard, guarding the border and collecting tax on the export of goods. Farmers' rice taxes were collected at a collection center set up in the village office. In the bays, officials were placed just like in the villages, and at the ports, there were officials dispatched by the feudal domain called "buichiyaku" who collected fishing taxes and commodity taxes. Ordinary people organized into five-man groups and lived a life of mutual assistance and collective responsibility.

The domain government was run by this system of offices, but Nonaka Kaneyama's rule came to an end due to public discontent and the impeachment of his political opponents, ushering in a period of change in domain government known as the Kanbun Reforms. From then on, domain government remained relatively peaceful until the implementation of the monopoly system in 1752 (the second year of the Horeki era). Domain government tended to be governed more civilly under a council system, but during this time, local fiefs were changed to storehoused rice fiefs, equal exemptions were implemented to average out annual tributes, and the Tenna Reforms (1681) were implemented, marking the completion of the domain government's period of rule. The promulgation of the Genroku Ojomoku (Great Rules of the Genroku Era) signaled this, but the Shogunate's taxes and the Hoei earthquake put pressure on the domain's finances, and the domain's government began to falter as the Horeki period (1751-1764) began. The implementation of a monopoly system from the Horeki to Tenmei periods (1781-1789) led to peasant uprisings, but the Tenmei reforms carried out by the ninth lord, Toyoyoshi, restored a measure of stability. However, the Tenpo famine dealt a major blow, and the thirteenth lord, Toyohiro, appointed Mabuchi Kahei and other members of the Okozegumi to embark on reforms of the domain's government, but these efforts were thwarted by suspicions that Kahei was a follower of Shingaku. Nevertheless, the Village Headman Alliance, which was formed during the Tenpo period (1830-1844), became a hotbed of the later Imperial Loyalist Movement, and the Tosa Domain appeared on the historical stage at the end of the Edo period. Yoshida Toyo, who was appointed by the 15th lord Toyonobu (Yodo), used his disciple Shin-Okoze-gumi as his hands and feet to carry out the Ansei Reforms, but he was counterattacked by anti-Yoshida conservative clans and the Tosa Loyalist Party led by Takechi Zuizan, and Yoshida was assassinated by a member of the Loyalist Party. From the Bunkyu period (1861-1864) to the Meiji Restoration, Yodo's union of the Imperial Court and the Shogunate and the claims of the Loyalist Party became intertwined and progressed, but the Tosa Domain played a role in changing the era with its proposal for the return of imperial rule, based on a plan proposed by Sakamoto Ryoma. During the Meiji Restoration, it became Kochi Domain, but in 1871 (Meiji 4) when the feudal domains were abolished and prefectures were established, Kochi Prefecture was established.

[Yamamoto Dai]

"Tosa Clan" by Michio Hirao (1965, Yoshikawa Kobunkan) " "Tosa Clan" by Dai Yamamoto (included in "Tales of Clan History 7", 1965, Jinbutsu Oraisha)"

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

江戸時代、土佐国（高知県）一国を領有した外様(とざま)藩。1600年（慶長5）関ヶ原の戦い後山内一豊(やまうちかずとよ)が土佐藩祖となってから、明治の版籍奉還、廃藩置県に至るまで、忠義(ただよし)、忠豊(ただとよ)、豊昌(とよまさ)、豊房(とよふさ)、豊隆(とよたか)、豊常(とよつね)、豊敷(とよのぶ)、豊雍(とよちか)、豊策(とよかず)、豊興(とよおき)、豊資(とよすけ)、豊煕(とよてる)、豊惇(とよあつ)、豊信(とよしげ)、豊範(とよのり)と16代続いた。石高(こくだか)は20万2600石余だが、実際は長宗我部(ちょうそがべ)検地の結果によると24万8300石余。これが本田高で、新田開発によって幕末維新のころは約50万石となった。高知藩ともいう。

　一豊は入国後、長宗我部遺臣（一領具足(いちりょうぐそく)）を弾圧あるいは懐柔(かいじゅう)し、中村、宿毛(すくも)、佐川、窪川(くぼかわ)、本山(もとやま)、安芸(あき)などの要地に一門・重臣を配して支配体制を整え、高知城を築き、城下町を設営した。2代忠義は野中兼山(けんざん)を用いて藩政の基礎を固めた。兼山は新田開発、港湾整備、殖産興業、専売仕法、郷士取り立てなどの政策を実施した。藩士は上士(じょうし)（家老、中老、馬廻(うままわり)、小姓(こしょう)組、留守居(るすい)組）と下士(かし)（郷士、用人、徒士(かち)、足軽、武家奉公人）に分かれ、階級差別は厳しかった。藩の政治は、家老のうちから任命される奉行職(ぶぎょうしょく)（執政(しっせい)）が統率したが、実務は中老や馬廻から任命される仕置役(しおきやく)（参政(さんせい)）とその下の各奉行があたり、裁判や警察は大目付が下級役職を統轄して行った。さらに藩主側近の近習(きんじゅ)家老がおり、江戸と京都には留守居役、大坂には大坂在役(ざいやく)が置かれ国元との連絡にあたった。民衆支配は町・郡(こおり)・浦の奉行がおり、その下で地域の行政事務を助けたのが庄屋(しょうや)である。高知城下には町会所が置かれ、総年寄、庄屋、年寄、総組頭などの町役人が町政をつかさどったが、豪商が総年寄となって庄屋以下を統率した。郡奉行は村役人を監督したが、村には庄屋・老(としより)（年寄）・組頭が置かれた。山間部の小村には名本(なもと)・老・組頭がおり、小村をあわせたものを郷といい、郷には大庄屋(おおじょうや)・総老・総組頭が置かれた。国境には道番所（関所）が設置され、大庄屋が番頭(ばんがしら)を、名本が番人を兼ねることが多く、国境を警備し、商品の移出には口銀(くちぎん)を取り立てた。農民の年貢米は村方役所に置かれた納所(なっしょ)に集められた。浦分にも村と同じく役人が置かれ、港には分一役(ぶいちやく)とよばれた藩派遣の役人がいて、漁業税や商品税を取り立てた。一般庶民は五人組を組織し、相互扶助と連帯責任を負った生活をしていた。

　こうした職制によって藩政は推進されたが、野中兼山の政治は民衆の不満と政敵の弾劾によって終わりを告げ、寛文(かんぶん)の改替(かいたい)といわれる藩政の転換期を迎えた。以後1752年（宝暦2）の専売制の実施まで藩政は比較的平穏に推移する。藩政は合議制のもとで文治的傾向が強くなるが、その間、地方知行(じかたちぎょう)から蔵米(くらまい)知行への転換、年々の貢租の平均化を図る平等免(ならしめん)が行われ、天和(てんな)の改革（1681）が実施されて藩政の完成期を迎える。「元禄大定目(げんろくおおじょうもく)」の公布はこれを意味するが、幕府の課役や宝永(ほうえい)の地震は藩財政を圧迫し、宝暦(ほうれき)期（1751～1764）に入って藩政は動揺し始める。宝暦から天明(てんめい)（1781～1789）にかけての専売制実施により農民一揆(いっき)が起こるようになるが、9代豊雍によって天明の改革が行われ、いちおうの安定を取り戻した。だが天保(てんぽう)の飢饉(ききん)は大きな打撃となり、13代豊煕は馬淵嘉平(まぶちかへい)らのおこぜ組を起用して藩政改革に乗り出したが、嘉平の心学嫌疑のため挫折(ざせつ)した。それにしても、天保期（1830～1844）に結成された庄屋同盟は後の勤王運動の温床となり、幕末に至って土佐藩は歴史の舞台に登場する。15代豊信（容堂）に起用された吉田東洋(とうよう)は門下の新おこぜ組を手足として安政(あんせい)の改革を断行するが、反吉田の保守門閥層と武市瑞山(たけちずいざん)を盟主とする土佐勤王党の反撃を受け、吉田は勤王党員に暗殺された。文久(ぶんきゅう)（1861～1864）から維新にかけて、容堂の公武合体と勤王党の主張とが絡み合いながら進展してゆくが、坂本龍馬(りょうま)の献策を基本とする大政奉還建白によって土佐藩は時代転換の役割を果たした。明治維新で高知藩となったが、1871年（明治4）廃藩置県により高知県として発足した。

［山本　大］

『平尾道雄著『土佐藩』（1965・吉川弘文館）』▽『山本大著「土佐藩」（『物語藩史 7』所収・1965・人物往来社）』

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