Fudai

Fudai daimyō (譜代大名^?) was a class of daimyōs who were hereditary vassals of the Tokugawa in Edo-period Japan. It was primarily the fudai who filled the ranks of the Tokugawa administration.

Many of the families who formed the ranks of the fudai daimyōs were families which had served the Tokugawa clan since before its rise to national primacy. Some of these include the Honda, Sakai, Sakakibara, Ii, Itakura, and Mizuno clans. Tokugawa Ieyasu's "Four Great Generals"—Honda Tadakatsu, Sakakibara Yasumasa, Sakai Tadatsugu, and Ii Naomasa—were all pre-Edo period fudai, and went on to become fudai daimyōs. In addition, some branches of the Matsudaira clan (from which the Tokugawa clan originated), while allowed to retain the Matsudaira surname, were fudai.

As Tokugawa Ieyasu rose to power in the 16th century, his domains increased, and as his domains increased, he began to hand out landholdings to his vassals, so that one by one, many of them became daimyōs. This was the birth of the fudai daimyō class. In contrast to the tozama, the fudai typically ruled small fiefs, many in strategic locations along the principal roads or in the Kantō region near the headquarters of the shogunate at Edo. High posts in the shogunate, such as Rōjū and wakadoshiyori, normally went to fudai. In addition, the post of Kyoto Shoshidai almost always went to a fudai daimyō.

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