Traditionally, tribal jurisdictions overlapped on the northern Great Plains. Tribes recognized each other as sovereign, and friendly or kin-related bands and tribes would occasionally share sovereignty over peripheral territories. Such nonexclusive territorial sovereignty stood in the way of an expanding United States. With conflicting conceptual frameworks of sovereignty, the sovereign United States and the sovereign tribes entered into treaties for cession of lands. As non-Indians settled onto the newly ceded lands, they pressured the new territorial states and the federal government for lands within Indian reservations. Non-Indians did not evenly exert pressure for lands. Reservations in greatest demand were generally opened for non-Indian settlement first. Once opened, tribes on these reservations lost much of their lands to the non-Indian settlers.