Tsukaiban were battlefield messengers and couriers. During the Edo Period they were inspectors, often acting as assistants to Metsuke. Often, Metsuke would be chosen from the ranks of Tsukaiban.
References
- Beerens, Anna. Interview with a Bakumatsu Official: A Translation from Kyuji Shimonroku Monumenta Nipponica, Vol. 55, No. 3. (Autumn, 2000), pp. 369-398.