 The structure was originally created to replace older guilds, known as "za", and by 1785, there were over one hundred "kabunakama" in Osaka alone, including a number granted special privileges by the shogunate, but taxed heavily in exchange.Some of these were groups entrusted and authorized to control the nation's trade in precious metals, iron, and copper.In the 1840s, "rōjū" Mizuno Tadakuni attempted to do away with the "kabunakama", in order to combat monopolies, but this and many of his other reforms were resisted so strongly by the merchants of Osaka (and others) that he was forced to abandon his efforts.