It was formed by merging the feudal lords (daimyō) and court nobles (kuge) into one system modelled after the British peerage.
Distinguished military officers, politicians, and scholars were occasionally ennobled until the country's defeat in the Second World War in 1945 (新華族, shin kazoku, lit.
[1] Itō Hirobumi, one of the principal authors of the Meiji constitution, intended the new kazoku peerage to serve as a political and social bulwark for the "restored" emperor and the Japanese imperial institution.
By the end of 1869, a pension system was adopted, which gradually displaced the kazoku from their posts as provincial governors and as government leaders.
The initial rank distribution for kazoku houses of kuge descent depended on the highest possible office to which its ancestors had been entitled in the imperial court.
Thus, the heirs of the five regent houses (go-sekke) of the Fujiwara dynasty (Konoe, Takatsukasa, Kujō, Ichijō and Nijō) all became princes, the equivalent of a European duke, upon the establishment of the kazoku in 1884.
Heads of families in the lowest three tiers (those in the ranks of urin, mei and han) typically became viscounts, but could also be ennobled as counts.
In 1891, the head of the Date-Uwajima family (Uwajima Domain), a cadet branch of the clan which had remained loyal to the Emperor during the conflict, was raised to the rank of marquess, having been ennobled as a count in 1884.
Under the Peerage Act of 7 July 1884, pushed through by Home Minister and future first Prime Minister Itō Hirobumi after visiting Europe, the Meiji government expanded the hereditary peerage with the award of kazoku status to persons regarded as having performed distinguished public services to the nation.
[1] The government also divided the kazoku into five ranks explicitly based on the British peerage, but with titles deriving from the ancient Chinese nobility.
Unlike in European peerage systems, but following traditional Japanese custom, illegitimate sons could succeed to titles and estates.
Since the end of the war, many descendants of the kazoku families continue to occupy prominent roles in Japanese society and industry.
[11] Some opted to be educated overseas, such as at Eton College (e.g., Prince Iesato Tokugawa) and Cambridge University (e.g., Marquess Masauji Hachisuka, Baron Koayata Iwasaki).
Those who followed rather unusual career paths included Marquess Hijikata Yoshi, who became a communist and fled to Soviet Russia, and Meiho Ogasawara, an heir to a viscountcy who pursued his passion for films and was disinherited in 1935.