Satomi Yoshiyasu

Satomi Yoshiyasu (1573 – December 18, 1603 [16th day of the 11th month of Keichō 8]) was a daimyo spanning the Azuchi-Momoyama period and the early Edo period. As head of the Satomi clan of Awa, he saw his house's fortunes fall and rise sharply under successive submission to the Toyotomi and Tokugawa regimes.

Succession

His father was Satomi Yoshiyori. When his father died in 1587, Yoshiyasu succeeded as head of the clan at the age of fifteen. He took a niece of Oda Nobunaga as his principal wife, seeking to strengthen his political footing through ties to the central authority.

The Odawara Campaign and Reduction

During the Odawara Campaign of 1590, Yoshiyasu incurred the anger of Toyotomi Hideyoshi and had his holdings in Kazusa and Shimōsa confiscated, leaving him only the single province of Awa. The koku assessment under the submitted land survey (sashidashi kenchi) is said to have been 40,000 koku. The reason for this punishment was traditionally explained as his late arrival at Odawara, but recent scholarship has shifted toward the view that he was called to account for violating Hideyoshi's sōbuji edict banning private warfare between daimyo: he crossed to the Miura Peninsula, moved troops independently, and issued prohibitions (kinsei). In either case, the Bōsō three-province domain built by his forebears was lost in this single episode.

Under the Toyotomi Regime

Even after the reduction, he served as a Toyotomi daimyo performing military service, and in 1591 he deployed to suppress the Kunohe Rebellion. In 1597 the Taikō land survey was carried out, and the koku assessment of Awa Province was revised upward to 91,000 koku.

Sekigahara and Tateyama Domain

In 1600 Yoshiyasu followed Tokugawa Ieyasu on the Aizu campaign and was responsible for the defense of Utsunomiya Castle. After the Battle of Sekigahara he was granted an increase of over 30,000 koku in Kashima District, Hitachi Province, and was ranked among the kunimochi daimyo under the Edo shogunate. Under the Tokugawa regime he was treated as lord of Tateyama Domain.

Death

In 1603, the very year the Edo shogunate was established, Yoshiyasu died at the age of 31. As a lord who experienced both the decline and the recovery of his house within a single generation, his early death is positioned as a prelude to the process by which the Satomi clan would later move toward attainder (kaieki).