1790 to 1860
T H E territory of the United States, huge and various, must be expected to have a history correspondingly complicated and diverse. It is one of the tasks of the historian to select and to simplify, but simplification, already hard, is made in this case still harder by the fact that the area described by the word 'America' kept on changing through several decades of the 19th century. The Declaration of Inde pendence, signed by 'the Representatives of the United States of America' in 1776, claimed independence not for the inhabitants of the 3 million square miles of the present-day United States, but for the inhabitants of 13 States on the eastern sea-board with a population of less than 4 million. Few of these individuals, except up a dozen or so river valleys, lived more than 100 miles from the sea. From this coastal base, American sovereignty was expanded right across the continent by three methods; pioneering, purchase, and war.