Tonya (also toiya) were merchant middlemen whose function in the cities was primarily wholesaling, either on commission or in their own name (which was more speculative). More of them moved toward the more speculative side of things as commerce grew in the Edo period. Along the Nakasendo and other highways, the freight managers were charged with maintaining the supply of porters and horses which were required for moving official travelers and freight along the road system. Many tonya became involved in the movement of strictly commercial goods and travelers along the highway or in the development of rural commercial operations including manufacturing. Sake brewing was typical. The tonya was usually the third most important man in a post-town, after the owners of the honjin and waki-honjin.
