In Tokugawa Japan, warriors constituted the ruling class, but only the highest-ranking samurai were able to hold and govern fiefs. The Tokugawa shoguns governed about one quarter of the country directly and granted the rest to relatives and powerful vassals. The country was thus fragmented into shogunal lands; about 270 domains ruled by lords (daimyō); the fiefs of lower-ranking vassals called bannermen (hatamoto); temple and shrine fiefs and other miscellaneous fiefs; and sub-fiefs of various kinds. While some domains were quite large and covered one province or more (the spatial unit of the province was a vestige of the ancient imperial state), most fiefs were smaller in size and their territories in many cases scattered. The spatial structure of warrior rule was relevant to the vaccination process because physicians required governmental support to mobilize recipients for the vaccine.

The land in Echizen province was divided into fiefs of many different sizes. Such fragmentation was not necessarily a problem as long as rural government concentrated on the collection of taxes, management of agriculture, and keeping the peace. But over the course of the Tokugawa period, the functions of government gradually expanded, and in the nineteenth century many rulers developed an interest in public health. The feudal, decentralized structure of government posed a major obstacle to the building of a public health infrastructure.

Within Echizen, there were six domains in the eighteenth and nineteenth century whose lords maintained headquarters directly in the province. Besides these six, there were several exclaves belonging to lords based outside of Echizen province, as well as shogunal territories and five small fiefs of bannermen (hatamoto). Even if the smallest miscellaneous fiefs are excluded, one arrives at a total of seventeen jurisdictions for this one province alone.

Fukui domain dwarfed all the other domains in Echizen with land holdings of 320,000 koku (a unit measuring the productivity of the land). Its lands were concentrated around the castle town of Fukui as well as in the western part of the province and along the coast. In addition, the Matsudaira lords of Fukui, who were a branch family of the Tokugawa, administered a large area of custodial land on behalf of the shogunate. At the same time, the Matsudaira had entrusted 20,000 koku of their land around the town of Fuchū to their most powerful house elder--the House of Honda--as a sub-fief. Despite the Honda's status as mere rear vassals, they governed their territory with a great deal of autonomy and were treated as quasi-daimyō (lords of a domain) in the shogunate's feudal hierarchy. Domain and town doctors in the castle town of Fuchū thus established their own chapter of vaccinators in 1850, though they maintained close ties to their colleagues in the castle town of Fukui [Umihara, 2007].

Other significant domains in Echizen province included Maruoka (50,000 koku), Sabae (50,000 koku; 40,000 after 1862), Ōno (40,000 koku), and Katsuyama (22,000 koku). Among these, Ōno domain features prominently in this module. The Doi family of Ōno governed four distinct patches of territory: a relatively coherent block around the castle town of Ōno, as well as two exclaves in the mountains in the eastern part of the province and one scattered exclave—the so-called Nishikata fief—in the Niu district near the Sea of Japan. East of Ōno and Katsuyama, there was a large mountainous area governed by the lord of Gujō domain, whose headquarters were in the town of Hachiman in neighboring Mino province.