The early seventeenth century saw the attempts of the Dutch East India Company (VOC) to become the sole European power with access to the Moluccas and to the clove and nutmeg originating there. Makassar, a trade entrepôt on South Sulawesi and the capital of the Sultanate of Gowa, increasingly became the centre of resistance against the Dutch monopolistic policies. Over the course of the seventeenth century, it became a harbour where European and Asian traders alike would come to buy their spices and trade other high-value goods and became a refuge for many Portuguese fleeing Dutch encroachment elsewhere in Asia. While Makassar was on the one hand a proud bandar, or free harbour, it also participated in the political and military scramble for the Moluccas, expanding its political influence there and thus preserving its continued access to these spices. This made Makassar both a trading port of choice and a valuable ally to other powers in the region, both Asian and European, which gave it both a strong impetus and the necessary channels for rapid military innovation. This chapter explores various aspects of the Portuguese role in Makassar’s military development, focusing on fort-building practices, weapons, and military expertise and it goes on to explore an episode of direct military cooperation between the Portuguese and the Makassars in the face of a Dutch attack.