In 1907, Japanese Rule in Formosa was published in London. It was the English translation of Taiwan tōchi shi (1905), a book about Japan's colonization of Taiwan by Japanese popular historian and liberal politician Takekoshi Yosaburō. Japanese Rule in Formosa proved remarkably influential, both at thetime and in postwar historiography. Although isolated quotes from the 1907 work are frequently used by present-day historians, little attention has beengranted to the political context in which it was published or the accuracy ofthe translation. The fact that Takekoshi advocated an unambiguous form of colonial rule in which the Japanese constitution would not apply in Taiwanplaced him at odds with other leaders of his liberal Seiyūkai party whowanted Taiwan to be merged into Japan’s administrative and legal structures.Takekoshi’s stance reveals that colonial debates did not always match up with other political or philosophical fault lines. His ideas were, however, consistent with his liberal worldview, and engaged in global, trans-imperial dialogue about assimilation and association in a colonial administration. This article will position Takekoshi’s work within the contemporaneous Japanese debate over Taiwan’s legal status and argue that, although the timing of its publication meant that it had little influence in Japan, it had a significanteffect on the attitudes of colonialist scholars in Europe and America towards Japanese imperialism.