Roju Hosho (老中奉書)
Roju Hosho was the official document issued by roju (a senior councilor of the Tokugawa shogunate) in the Edo period.
There were two types of Roju Hosho: the Rensho Hosho issued in the joint names of several roju and the Hosho issued by a single roju.
As the example of the former, there is the Rensho Hosho which was used when roju conveyed the shogun's order to daimyo (Japanese feudal lords) and ongoku-bugyo (the commissioners placed at the demesnes of the Tokugawa shogunate). As the example of the latter, there is the Hosho which was used for the confirmation of receiving the gifts to the shogun family.
On April 26, 1664, the system was changed. For minor matters, a single signature was put to the roju hosho.
The honorific title 'tono' (lord) was added after the name of an addressee and only the month and date were written as the issuing date, without including the year. The exception was the license to construct a castle, on which the year, month, and date were described.
The roju's names written as the senders were signed in the ascending order of their ranks.
Sometimes Roju sent a private letter to daimyo or hatamoto (direct retainers of the Edo bakufu). In this case, the honorific title 'sama' (Mr.) was added to the addressee's name to distinguish it from the roju hosho.