Charles W. A. Prior offers a new account of the sovereign claims of Native Americans, the Crown, and colonies in early America, arguing that Native American diplomacy shaped how sovereignty was negotiated and contested among all three, from Virginia's founding to the ratification of the U.S. Constitution. Previous scholars have focused on the contested relationship between the British imperial state and the colonies it established along the Atlantic Coast without addressing how sovereign Native nations shaped the colonial process through warfare, diplomacy, trade, peace-making, and treaty-making. Prior adopts a new interpretive framework for examining sovereignty in early America, arguing that the Native and colonial spaces of the Northeast were a treaty ground thickly layered with agreements and negotiated rules of interaction. Drawing on an extensive range of treaty records, writings on colonial and imperial affairs, letters, and official documents, Treaty Ground argues that sovereignty was negotiated within diplomacy and shaped the norms of war, the terms of peace and alliances, the rightful ownership of territory, and appropriate responses to treaty violations. This process in turn structured relations between the Crown and colonies and framed initial positions on how the power of congress related to that of the states. Treaty Ground offers historical depth to our understanding of how Native nations articulated Indigenous power within colonialism, cuts settler colonialism down to size, and expands contemporary understandings of the sovereign relationships between Native nations in the United States and Canada.