This paper seeks to answer the question of how the sultanates of Malaysia maintained their authority in the current nation-state era as almost all of Indonesia's hundreds of sultanates (except for the Sultanate of Yogyakarta in Java) lost formal power. It proposes three findings. First, Dutch and British colonialism had different legacies in Indonesia and Malaysia, respectively. Second, following their independence, Indonesia and Malaysia adopted different government systems, with the former becoming a unitary republic and the latter becoming a federal state; consequently, the sultanates of Indonesia had to submit themselves to the central government in Indonesia, whereas those in Malaysia were given broader space to exercise their authority within a federal state. Third, the sultanates of Malaysia have a two-layered identity, resulting from the convergence of ethnic Malay and Islamic identities that eventually strengthened the Sultanate's authority and legitimacy in the eyes of the people and the federal state; conversely, convergence between ethnic and religious identity was limited in Indonesia's sultanates, subsequently undermining the sultans' ability to uphold authority and power. © Koninklijke Brill NV, Leiden, 2020