Abstract
The Dutch conquest of Spanish Formosa in 1642 initiated an island-wide colonial expansion of Dutch East India Company (VOC) in Taiwan. For the purpose of connecting Tayouan in the core area and northern Formosa, Tamsuy, the nearest settlement in the region, played a pivotal role in Company's formulation on the newly acquired territories. The author proposes that three stages can be observed in this process: Quelang over Tamsuy, 1642-1643; a transitional period, 1644-1645, and Tamsuy over Quelang, 1645-1662.In August, 1645, the introduction of opperhoofd in Tamsuy marked the changing center of power and authority in northern Formosa. Quelang gradually won its military tone. In order to open the Tamsuy Route between Tayouan and Tamsuy, the Dutch authorities made efforts to defeat aboriginal villages along the region, including the powerful Quataongh. These conquests, creating more leasehold divisions into the village leasehold system, made more profits in accordance with the status quo as 'the sole master in the whole island'. However, by the end of 1650s, northern Formosa failed to continuously lure the Dutch, due to financial hardship, difficulties in maintenance and supply, as well as unpleasant environment for the Dutch residents. The Dutch reluctance to retain this burden of northern Formosa was to prevent the presumed occupation by the local Chinese who had been encouraged to settle down in this region by the authorities but now might incite the Formosans to resist the Company.