As elsewhere in Tokugawa Japan, Ōno's domain population was divided into semi-autonomous groups that situated subjects in public life by assigning them a status identity. Although these groups displayed great diversity, they can be subsumed into three broad hereditary categories: samurai, commoners (townspeople and villagers), and outcastes. The three categories constituted not just social spaces with distinct norms and customs, but to some extent could be mapped onto physical space because their members often lived together in separate sections of castle towns. They thus constituted “places,” both in a physical and a socio-political sense. While the boundary between commoners and samurai was relatively porous—marriages between the two, for example, were common—outcastes experienced major discrimination in everyday life. Commoners typically avoided intermarrying with outcastes and did not allow people from outcaste lineages to live in their midst. Many believed that outcastes suffered from hereditary stigma.

Could the smallpox vaccine cross the boundary between commoners and outcastes? The smallpox virus, after all, did not discriminate by status. It infected both high and low, and the children of outcastes, too, needed to be vaccinated if the goal was to eradicate the disease. On the other hand, vaccination with the cowpox virus was a social transaction, and one involving the transfer of bodily fluids. This posed a problem because many people in Ōno domain believed that outcaste status was inherited at birth and determined by lineage (Ehlers 2018, 109-111). In the second half of the Tokugawa period, most physicians believed that the quality of at least one bodily fluid—blood—had the potential to permanently influence the quality of one's bloodline (Burns 2019, 47-73). Let us examine the context in which domain officials and physicians tried to reconcile the biological and social reality to allow for the possibility of outcaste vaccinations.

The first (and only) time the issue comes up in local sources was in 1860, about ten years into Ōno's vaccination program. In the 10th lunar month of 1860, the domain government issued orders to deal with a flurry of smallpox outbreaks that had recently occurred among the townspeople (Town elders' journal of 1860.10.6 and 10.8, in Ōno shishi hensan iinkai 1995, 862-63). It had come to the administration's attention that townspeople sometimes concealed such outbreaks, and officials thus ordered the town population to strictly report all cases and not let any patients out of the house while still covered in scabs to reduce the risk of contagion. The domain then extended this order to the entire domain, and threatened both townspeople and villagers with punishment if they failed to report an occurrence of smallpox to the vaccination clinic. The domain also admonished all subjects not to take any children without immunity to the house of a child suffering from smallpox. A month later it ordered the expulsion of beggars from the town who showed symptoms of infection (Town elders' journal of 1860.11.6, in Ōno shishi hensan iinkai 1995, 867).

These orders suggest that the domain's earlier order to punish the parents of smallpox patients may have had the unintended effect of discouraging people from reporting outbreaks. Despite all efforts, the disease had not been eradicated by 1860, and the government had to acknowledge that fact and issue quarantine rules to minimize contagion. In addition, the government now sought to address a constituency it had so far neglected: the children of local outcastes.

There were two groups of hereditary outcastes living on the periphery of Ōno town: the Koshirō (beggar bosses) and the Kawaya/Eta (leather workers). Their population was small—between thirty and forty in the case of the Koshirō and even fewer in the Kawaya's case. On 10/6 of 1860 (lunisolar calendar), the domain government ordered the town elders to identify any unvaccinated children among the beggar bosses and leather workers, and to inform them that the domain intended to vaccinate them. The government would get back to them later to announce the location.

Apparently, domain officials knew or suspected that the children of outcastes had so far not (or not sufficiently) been exposed to vaccinations—perhaps because they were being rejected at the clinic, or because their parents lacked interest or anticipated being excluded. This posed a risk to all children in the domain who remained unvaccinated for the time being. By 1860, the domain government seems to have been determined to include outcastes in the program. But the order also suggests that officials intended to have outcastes' children vaccinated not at the clinic but at a separate location, possibly to prevent them from becoming “pox bases” for commoner and samurai children and offending the discriminatory sentiments of parents.