The Castle That Defied the Shogunate's One-Castle Rule
In 1615 the Tokugawa shogunate issued the ikoku-ichijo-rei — the 'one castle per domain' law — requiring all daimyo to demolish excess castles. Virtually every lord complied immediately. Shiroishi Castle is the extraordinary exception: the Katakura clan, senior retainers of the powerful Date clan of Sendai, were granted special permission to maintain it. This unique dispensation, granted only here, makes Shiroishi historically remarkable among Tohoku castles.