Diplomatic relations between the Ottoman Empire and the Sultanate of Aceh (today a province in north-west Indonesia), which had begun in the sixteenth century but then subsequently neglected over the next two centuries, were reinvigorated in the 1840 s when the expanding Dutch colonial empire arrived on the borders of Aceh. When the Acehnese sought to revive the defunct relations with Istanbul, they were met with an ambivalent Ottoman response. Ottoman statesmen seemed torn between the potential benefits of the suggested cooperation and the perils of antagonizing Western colonial powers in the region. Ambivalence also characterized the Ottomans' response to the Acehnese request for Ottoman suzerainty over their territories in 1868-9, in 1872-3 on the eve of the Dutch invasion of their country, and in the aftermath, for fear of consequent conflict with the Great Powers. By reconstructing the history of Aceh-Ottoman diplomatic interactions on the basis of hereto unexplored Ottoman records, this article aims to reinstate not only the Acehnese, but also the Ottomans as agents in their own right, during a period of Western colonialist expansion. As such, it seeks to decenter historical narratives of nineteenth-century interstate relations, traditionally based on European sources and perceptions, which mostly ignore the agency and diplomatic interactions of non-Western powers.