{{Italic title, reason= :Japanese words and phrases ''Seishitsu'' (正室) is the

Japanese Japanese may refer to: * Something from or related to Japan, an island country in East Asia * Japanese language, spoken mainly in Japan * Japanese people, the ethnic group that identifies with Japan through ancestry or culture ** Japanese diaspor ...

term of the

Edo period The , also known as the , is the period between 1600 or 1603 and 1868 in the history of Japan, when the country was under the rule of the Tokugawa shogunate and some 300 regional ''daimyo'', or feudal lords. Emerging from the chaos of the Sengok ...

for the official

wife A wife (: wives) is a woman in a marital relationship. A woman who has separated from her partner continues to be a wife until their marriage is legally dissolved with a divorce judgment; or until death, depending on the kind of marriage. On t ...

of high-ranking persons. The tennō,

kugyō is the collective term for the very few most powerful men attached to the court of the Emperor of Japan in pre-Meiji eras. The term generally referred to the and court officials and denoted a court rank between First Rank and Third Rank un ...

(court officials), ''

shōgun , officially , was the title of the military rulers of Japan during most of the period spanning from 1185 to 1868. Nominally appointed by the Emperor, shoguns were usually the de facto rulers of the country, except during parts of the Kamak ...

'' and ''

daimyō were powerful Japanese magnates, feudal lords who, from the 10th century to the early Meiji era, Meiji period in the middle 19th century, ruled most of Japan from their vast hereditary land holdings. They were subordinate to the shogun and no ...

s'' often had several wives to ensure the birth of an heir. The ''seishitsu'' had a status above other wives, called ''sokushitsu'' (側室,

concubine Concubinage is an interpersonal relationship, interpersonal and Intimate relationship, sexual relationship between two people in which the couple does not want to, or cannot, enter into a full marriage. Concubinage and marriage are often regarde ...

). The system dates back to the

ritsuryō is the historical Japanese legal system, legal system based on the philosophies of Confucianism and Legalism (Chinese philosophy), Chinese Legalism in Feudal Japan. The political system in accord to Ritsuryō is called "Ritsuryō-sei" (). ''Kya ...

system in the

Nara The National Archives and Records Administration (NARA) is an independent agency of the United States government within the executive branch, charged with the preservation and documentation of government and historical records. It is also task ...

and

Heian period The is the last division of classical Japanese history, running from 794 to 1185. It followed the Nara period, beginning when the 50th emperor, Emperor Kammu, moved the capital of Japan to Heian-kyō (modern Kyoto). means in Japanese. It is a ...

s. At the time, the main wife was called ''chakusai'' (嫡妻). The last Japanese emperor to have official concubines was

Emperor Meiji , posthumously honored as , was the 122nd emperor of Japan according to the List of emperors of Japan, traditional order of succession, reigning from 1867 until his death in 1912. His reign is associated with the Meiji Restoration of 1868, which ...

. Succession disputes between sons of the official wife and concubines were a constant source of internal, often armed conflict within houses (

O-Ie Sōdō O-Ie Sōdō (, "house strife") were noble family disputes within the samurai and aristocratic classes of Japan, particularly during the early Edo period (17th century). The most famous is the ''Date Sōdō'', which broke out among the Date family in ...

See also