|Parent house||Isa clan|
|Current head||Date Yasumune|
|Founding year||c. 1189|
|Ruled until||1871, Abolition of the han system|
|Cadet branches||Tamura clan (restored)|
The Date family was founded in the early Kamakura period (1185-1333) by Isa Tomomune who originally came from the Isa district of Hitachi Province (now Ibaraki Prefecture), and was a descendant of Fujiwara no Uona (721-783) in the sixteenth generation. The family took its name from the Date district (now Date City in Fukushima Prefecture) of Mutsu Province which had been awarded in 1189 to Isa Tomomune by Minamoto no Yoritomo, the first Kamakura sh?gun, for his assistance in the Genpei War and in Minamoto no Yoritomo's struggle for power with his brother, Minamoto no Yoshitsune.
During the Nanboku-ch? Wars in the 1330s, the Date supported the Imperial Southern Court of Emperor Go-Daigo through Kitabatake Akiie, who had been appointed Commander in Chief (or Chinjufu Sh?gun) of the Defense of the North, by the emperor.
As warlords gained and lost power in the Sengoku period, trying to unite the country, the Date, along with a handful of other powerful families, did all they could to retain independence and dominance over their section of the land (in the case of the Date, the far north). Though not gaining the fame or power of the likes of Oda Nobunaga, Uesugi Kenshin, or Toyotomi Hideyoshi, they resisted the invasions of these warlords into the north. Date Masamune (1567-1636) contributed in particular to this effort, consolidating the families of the north into alliances against the major warlords. In 1589, Masamune with the help of former Ashina's samurai, Inawashiro Morikuni, seized the Aizu Domain of the Ashina at the Battle of Suriagehara; and he installed himself at Kurokawa Castle in Wakamatsu Province. However, the following year, Hideyoshi triumphed over the H?jo of Odawara; and Hideyoshi then obliged Masamune to be content with the fief of Yonezawa (300,000 koku).
Masamune ultimately gained some degree of independence by supporting Tokugawa Ieyasu. Ieyasu granted the Date much of the north, and yet the Date were not fully trusted. Despite the Date contribution of reinforcements for the Tokugawa during the battle of Sekigahara, the Date were viewed as a threat. In the Edo period, the Date were identified as one of the tozama or outsider clans, in contrast with the fudai or insider daimy? clans which were hereditary vassals or allies of the Tokugawa clan.
In 1600, Ieyasu charged the Date to fight against Uesugi Kagekatsu; and, with the assistance of Mogami Yoshiteru, Masamune's forces defeated Naoe Kanetsugu. In recognition of this success in battle, Masamune was granted the fiefs in twelve districts which had been held until that time by the Uesugi clan. The Date established themselves at Sendai (620,000 koku). By 1658, Masamune changed the name of the Uesugi's castle at Iwatezawa to Sendai Castle. The feudal daimy? were sometimes identified with the suffix "-k?" (duke, ruler of the land), preceded by the name of a place or a castle, e.g., Sendai-k? was one of the names by which Date Masamune was known.
Succession disputes erupted; there were a number of direct descendants of Masamune, and many kinsmen and hereditary vassals of the Date who resided nearby held estates of at least 10,000 koku, and thus had some influence. In 1660, Date Tsunamune was arrested in Edo, for drunkenness and debauchery; the charges were generally believed to have been true. Tsunamune was condemned to excavate the moats which encircled the sh?gun's Edo Castle. In 1660, he was ordered to supervise and pay for enhancing the north-east moat running from Megane-bashi to the Ushigome gate. The initial charges of licentious living are now believed to have been encouraged heavily by certain vassals and kinsmen in the north. These vassals and kinsmen appealed to the Council of Elders in Edo that Tsunamune should not be considered fit to rule, and that his son Date Tsunamura, great-grandson of Masamune, should become the daimy? (lord) of the Date han (fief). Thus, Tsunamura became daimy?, under the guardianship of his uncles, Date Munekatsu and Muneyoshi.
Ten years of violence and conflict followed in the north, reaching a climax in 1671 when Aki Muneshige, a powerful relative of the Date, complained to the shogunate of the mismanagement of the fief under Tsunamura and his uncles. The episode that followed is so complex and dramatic as to warrant becoming a well-known story known as the Date S?d? (Date Disturbance) and a theatrical play as well. Aki was summoned to Edo to argue his case before various councils and officials, and was involved in a number of interrogations, examinations and meetings, as were several other retainers of the Date. One retainer in particular, Harada Munesuke, was a supporter of Tsunamura and his uncles and, it is said, made a poor impression at Edo. At one point, Aki came upon Harada waiting to meet with some of the officials, and Aki began shouting insults. Swords were then drawn, and Aki was killed. Harada was killed moments after, by the officials or their guards. The official verdict was that Harada drew first; the Harada family was disbanded and though Tsunamura was affirmed as the proper daimy?, his uncles were punished.
The branches of the tozama Date clan include the following:
In the Edo period, T?zen-ji was considered the family temple of various clans, including the Date clan of Sendai. Other clans considering T?zen-ji to have been a clan temple were the Ikeda clan of ?mi Province, the Inaba clan of Usuki Domain in Bungo Province, the Suwa clan of Shinsh?, the Tamura of Ichinoseki, and the M?ri clan of Saeki in Bungo Province.
The Date clan's tutelary shrine, Kameoka Hachimang?, survives as a local shrine in Sendai.
Notable members of the clan listed by their date of birth, excluding clan leaders:
They were born to the Date clan but were nominally adopted by other families. The first name is the person who was nominally adopted.
These families were vassals of the Date clan. Notable members are listed by their date of birth.