An imam banished from eastern Indonesia to the Cape of Good Hope in 1780 builds a new Muslim community with a mix of fellow exiles, enslaved people, and even the men tasked with supervising his detention. Nineteenth-century colonial chroniclers invent the legend of the "loyal Malay" warrior, whose anger can be tamed through the "mildness" of British rule. A Tunisian-born teacher who arrived in Java from Istanbul in the early twentieth century becomes an enterprising Arabic-language journalist caught between competing nationalisms. Telling these stories and many more, Michael Francis Laffan offers a sweeping exploration of two centuries of interactions among Muslim subjects of empires and future nation-states around the Indian Ocean world. Under Empire traces interlinked lives and journeys, examining engagements with Western, Islamic, and pan-Asian imperial formations to consider the possibilities for Muslims in an imperial age. It ranges from the dying era of the trading companies in the late eighteenth century through the period of Dutch and British colonial rule up to the rise of nationalist and cosmopolitan movements for social reform in the nineteenth and twentieth centuries. Laffan emphasizes how Indian Ocean Muslims by turns asserted loyalty to colonial states in pursuit of a measure of religious freedom or looked to the Ottoman Empire or Egypt in search of spiritual unity. Bringing the history of Southeast Asian Islam to African and South Asian shores, Under Empire is an expansive and inventive account of Muslim communal belonging on the world stage.