Sasaki Moritsuna (佐々木盛綱)

Moritsuna SASAKI was a Japanese military commander who lived from the end of the Heian period to the beginning of the Kamakura period. He was also called Moritsuna KAJI.

He was born as the third son of Hideyoshi SASAKI who was the head of the Sasaki clan of Uda-Genji (Uda-Gen clan) in Omi Province. His childhood name was Hidetsuna. Moritsuna who had served MINAMOTO no Yoritomo since he had stayed in Izu Province as an exile followed the army raised by Yoritomo and played an active role in the Jisho-Juei War. In the Battle of Fujito in Kojima of Bizen Province, he defeated TAIRA no Yukimori who had confined himself to an island.

Moritsuna is featured in Yokyoku (a Noh song) "Fujito" which is chanted in a Noh play, "the Battle of Fujito," and a Kabuki play "Omi-Genji Senjinyakata."


All the dates in the text are indicated according to old lunar calendar. An era name after change is used for any year in the middle of which the name of an era has changed.

The Genpei War

Moritsuna was born as the third son of Hideyoshi SASAKI who was the head of the SASAKI clan of UDA-GENJI based at Sasakinosho in Omi Province. Due to the defeat of MINAMOTO no Yoshitomo whom Morituna's father followed in the Heiji War in 1159, Hidetsuna (name of Moritsuna before Genpuku (coming-of-age ceremony)) escaped to the Kanto region with his family and was protected by Shigekuni SHIBUYA. After having Genpuku and changing the name to Moritsuna, he came to serve MINAMOTO no Yoritomo who was a bereaved child of Yoshitomo and had been exiled to Izu Province at the age of 16.

On August 6, 1180, Moritsuna was ordered to come to a private room of Yoritomo who made up his mind to defeat the Taira clan, and was told about a plan to raise an army. At that time, Yoritomo said to Moritsuna, "Although I don't tell it to anyone yet, I tell my plan to you because I absolutely trust you." The above episode showed that Moritsuna was very much trusted by Yoritomo from the beginning even though Yoritomo told the same thing to other retainers such as Shigemitsu KUDO, Sanehira DOI, Yoshizane OKAZAKI, Tokage AMANO and Kagekado KATO.

On August 17, 1180, the day of raising an army, Moritsuna's older brothers killed Nobuto TSUTSUMI who was considered to act as guardian of Kanetaka YAMAKI and a brave warrior, and then, Moritsuna went to Kanetaka's residence with Kagekado and cut off his head. Although he accompanied Yoritomo to Sagami Province on August 20, 1180, Yoritomo's army was defeated in the Battle of Ishibashiyama. When Moritsuna and his old brothers fled to the residence of Shigekuni SHIBUYA who had taken the side of the Taira clan in the Battle of Ishibashiyama, Shigekuni welcomed them, sheltered them in a warehouse and offered hospitality. When Yoritomo who had fled to Awa Province rose a force of soldiers again and entered Kamakura, Moritsuna and his old brothers rushed to Yoritomo again. Moritsuna and his old brothers defeated the Taira clan in the Battle of Fujigawa on October 20, 1180, and were granted a former territory of Sasakinosho in the grant of honors held on August 23, 1180 at the provincial capital of Sagami Province for the first time after the raising of army. On November 4, 1180, Moritsuna also participated in a battle with Hideyoshi SATAKE caused at the provincial capital of Hitachi Province.

On June 7, 1182, he took care of Kagekado KATO who got falling-down drunk at a drinking party at Yuigahama. On October 17, 1182, Moritsuna became one of palanquin bearers when MINAMOTO no Yoriie, Yoritomo's legitimate son, moved from ubuya (a hut for delivering babies) to a residence on the palanquin.

In December 1184, Moritsuna was in Kojima of Bizen Province to search and kill the Taira clan, and on December 7, 1184, he captured a castle which was held by more than 500 horse soldiers led by TAIRA no Yukimori. The battle called the Battle of Fujito was also described in the "Heike Monogatari (The tale of the Heike)," and according to the Heike Monogatari, Moritsuna, who got information from a fisherman about a ford which was shallow enough for horses to cross, rode across the sea by cutting through the waves and took the lead in invading an island to which Yukimori confined himself. In addition, it is told among the local people that Moritsuna killed the fisherman to keep his mouth shut.

Shogunal retainers (of the Kamakura bakufu) in Kamakura

Under circumstances where a confrontation between MINAMOTO no Yoritomo and his younger brother, MINAMOTO no Yoshitsune, got more serious after the fall of the TAIRA clan, Yoritomo held a memorial service for his father, MINAMOTO no Yoshitomo, on October 24, 1185, and Moritsuna also attended it. On October 24, 1186, Moritsuna accompanied Yoritomo on his visit to Amanawa-jinja Shrine. On July 10, 1188, he joined a ceremony of MINAMOTO no Yoriie's first wearing armor. On August 15, 1190, Moritsuna accompanied Yoritomo on his visit to Tsurugaoka Hachiman-gu Shrine.

On July 20 of the same year, there occurred an incident that Nobuzane KAJI, 15-year-old son of Moritsuna, hit Suketsune KUDO on the forehead with a stone while they were palying a game of Sugoroku at Yoritomo's residence, and Suketsune got bleeding. Although he chased Nobuzane who escaped from there, Moritsuna was ordered by Yoritomo to capture Nobuzane on the following day. However, Moritsuna said that he disowned his son, Nobuzane, because Nobuzane had already run away and become a priest. When Yoritomo ordered Moritsuna to apologize to Suketsune, Moritsuna refused to apologize on the grounds that he had already disowned his son.

From September to November 1190, Moritsuna who accompanied Yoritomo on his going to Kyoto also accompanied Yoritomo on his visit to the Imperial Palace, to Iwashimizu Hachiman-gu Shrine, and so on. On October 1, 1191, Moritsuna presented 15 cows produced in Oshu (Mutsu Province) and Echigo Province to Yoritomo. On November 15, 1192, he accompanied Yoritomo on his visit to Eifuku-ji Temple Ruins. On September 7, 1193, Moritsuna was appointed to Tonoi (guard) of the Imperial Palace which had been devastated after the death of the Emperor Goshirakawa. On February 2, 1194, he attended a genpuku (attainment of manhood) ceremony for Yasutoki HOJO, and on November 21 of the same year, he participated in kasagake (horseback archery competition) held as one of Shinto rituals at Mishima-taisha Shrine.

On April 10, 1195, Moritsuna accompanied Yoritomo on his visit to the Imperial Palace when Yoritomo came to Kyoto for memorial service for Todai-ji Temple, and he was appointed as Hyoe no jo (Lieutenant of the Middle Palace Guards) at this time. On May 20, 1195, he also accompanied Yoritomo on his visit to Tenno-ji Temple.

On March 22, 1199 after Yoritomo died, Moritsuna had already entered into priesthood, and called himself Sainen. On April 3, 1201, Sainen who was in Isobe-go of Kozuke Province was ordered to subdue a rebellion raised by Sukemori JO and Hangaku Gozen. After receiving the order on April 5, 1201, Sainen fought a fierce battle with Sukemori JO who stood ready to fight at Tossaka-jo Castle in Echigo Province, before defeating him (Kennin War). In the Makishi Incident, he joined the army to defeat Tomomasa who was in Kyoto, on leap July 26, 1205.

Although the date of Moritsuna's death is unknown, there remains a grave in Kurashiki City, where, it is told, Moritsuna was buried.