American Indians lived in America before the Europeans arrived. There were, and still are, many nations and tribes of American Indians. Each tribe has different religions, customs, and languages. Europeans arrived in America in the 1500s and later. Life changed for the American Indians who met the Europeans. Colonial settlers spread disease to American Indians. Settlers fought American Indians and took their land. American Indians reacted in different ways to the Europeans. Some American Indians helped them. Some tribes signed treaties that gave land to the Europeans. Other tribes fought against Europeans in wars over land. American Indians lived in America before the Europeans arrived.