Per the UK publisher William Collins's promotional copy: "There is a quarter of this planet that is often forgotten in the histories told in the West. This quarter is oceanic, pulsating with winds and waves, tides and coastlines, islands and beaches. The Indian and Pacific Oceans constitute that forgotten quarter, brought together here for the first time in sustained history work." More specifically, Sivasundaram's aim in this book is to revisit the Age of Revolutions and Empire from the perspective of the Global South. Waves Across the South range from the Arabian Sea across the Indian Ocean to the Bay of Bengal and onward to the South Pacific, and Australia's the Tasman Sea. As the Western empires (Dutch, French, but mainly British) reached across these vast regions, echoes of the European revolutions rippled through them and encountered a host of indigenous political developments. Sivasundaram also opens the door to new and necessary conversations about environmental history and the consequences of historical violence, the extraction of resources, and the indigenous futures that Western imperialism cut short.