This article investigates cotton promotion policies in colonial Korea, with a focus on the role of a series of semi-governmental organizations (SGOs) in implementing colonial policies to shape farmers’ interactions with global, capitalist markets. Colonial attempts to develop the cultivation of cotton, a quintessential commodity of modern capitalism, highlight the incorporation of the Korean countryside into imperial networks of commercial commodity production and circulation. However, despite appeals to the rhetoric of capitalism and the expected response of profit-maximizing cotton cultivators, in practice colonial cotton campaigns relied on the active intervention of the colonial state to reinforce the adoption of new scientific and commercial agricultural practices. SGOs performed multiple roles in the promotion of cotton cultivation—distributing resources, defining expertise, regulating the production and sale of cotton, and attempting to change the behaviour of cotton cultivators, landlords, and even merchants in line with the colonial government’s strategic interests. As such, SGOs represent an understudied extension of the colonial state into the rural economy, which influenced the conditions under which farming households engaged in the commercial cultivation of cotton.