is the name of a former province of Japan in the area that is today Kōchi Prefecture

Kochi Prefecture

is a prefecture of Japan located on the south coast of Shikoku. The capital is the city of Kōchi.- History :Prior to the Meiji Restoration, Kōchi was known as Tosa Province and was controlled by the Chosokabe clan in the Sengoku period and the Yamauchi family during the Edo period.- Geography...

 on Shikoku

Shikoku

is the smallest and least populous of the four main islands of Japan, located south of Honshū and east of the island of Kyūshū. Its ancient names include Iyo-no-futana-shima , Iyo-shima , and Futana-shima...

. Tosa was bordered by Iyo

Iyo Province

was an old province of Japan in the area that is today Ehime Prefecture on Shikoku. Iyo bordered on Awa, Sanuki, and Tosa Provinces. It was sometimes called ....

 and Awa

Awa Province (Tokushima)

was an old province of Japan in the area that is today a part of Tokushima Prefecture on Shikoku. Awa was bordered by Tosa, Sanuki, and Iyo Provinces. It was sometimes called .-References:...

 Provinces. It was sometimes called .

History

The ancient capital was near modern Nankoku

Nankoku, Kochi

is a city located in Kōchi, Japan. Strong in the fishing industry and the market industry, Nankoku-shi supplies most of Kochi's agricultural needs, because of the amount of fields and plantations. Nankoku-shi's downtown is relatively small, has 2 major supermarkets, one major hospital, a tractor...

. Tosa jinja

Tosa jinja

, also known as Tosa nimasu jinja, Tosa takakamo Taisha, is a Shinto shrine located in the west of Kōchi in Kōchi Prefecture in Japan.Japan's government has designated the sanctuary as an Important Cultural Property.-History:...

 was designated as the chief Shinto shrine (ichinomiya) for the province].
Tosa was ruled by the Chōsokabe clan

Chosokabe clan

The was a Japanese samurai clan of the Sengoku period, that controlled Tosa Province , and later Shikoku Island. The clan is sometimes also known as...

 during the Sengoku Period

Sengoku period

The or Warring States period in Japanese history was a time of social upheaval, political intrigue, and nearly constant military conflict that lasted roughly from the middle of the 15th century to the beginning of the 17th century. The name "Sengoku" was adopted by Japanese historians in reference...

, and Chōsokabe Motochika

Chosokabe Motochika

was a Sengoku period daimyo in Japan. He was the 21st chief of the Chōsokabe clan of Tosa Province . He was the son and heir of Chōsokabe Kunichika and his mother was a daughter of the Saitō clan of Mino Province....

 briefly unified Shikoku

Shikoku

is the smallest and least populous of the four main islands of Japan, located south of Honshū and east of the island of Kyūshū. Its ancient names include Iyo-no-futana-shima , Iyo-shima , and Futana-shima...

 under his rule, although he was reduced to Tosa again by Toyotomi Hideyoshi

Toyotomi Hideyoshi

was a daimyo warrior, general and politician of the Sengoku period. He unified the political factions of Japan. He succeeded his former liege lord, Oda Nobunaga, and brought an end to the Sengoku period. The period of his rule is often called the Momoyama period, named after Hideyoshi's castle...

 and dispossessed entirely after Sekigahara

Battle of Sekigahara

The , popularly known as the , was a decisive battle on October 21, 1600 which cleared the path to the Shogunate for Tokugawa Ieyasu...

. The province was then granted to Yamauchi Kazutoyo

Yamauchi Kazutoyo

' also spelled Yamanouchi , was born the son of Yamanouchi Moritoyo in Owari Province at the end of the Sengoku period of Japan. Kazutoyo held the title of Tosa no kami....

. Tosa was a relatively poor province, and lacked a strong castle town even under the Chōsokabe. After Sekigahara, the castle town of Kōchi

Kochi, Kochi

is the capital city of Kōchi Prefecture on Shikoku island of Japan.Kōchi is the main city of the prefecture with over 40% of its population. As of May 31, 2008, the city had an estimated population of 340,515 and a density of...

 was established and remains the main city to this day. During the Edo Period

Edo period

The , or , is a division of Japanese history which was ruled by the shoguns of the Tokugawa family, running from 1603 to 1868. The political entity of this period was the Tokugawa shogunate....

 the province was controlled by the Tosa Domain

Tosa Domain

The was a feudal domain in Tosa Province of Japan during the Edo period. Its official name is . Some from the domain played important roles in events in the late Tokugawa shogunate...

.

Sakamoto Ryōma

Sakamoto Ryoma

was a leader of the movement to overthrow the Tokugawa shogunate during the Bakumatsu period in Japan. Ryōma used the alias .- Early life :Ryōma was born in Kōchi, of Tosa han . By the Japanese calendar, this was the sixth year of Tenpō...

 of the Bakumatsu era was born in Tosa.

Samurai from Tosa were important in the Meiji Restoration

Meiji Restoration

The , also known as the Meiji Ishin, Revolution, Reform or Renewal, was a chain of events that restored imperial rule to Japan in 1868...

of 1868.