ABSTRACT
The United States is one of the largest countries in the world with a population of more than 250 million living on a land area of over 9,350,000 square kilometres stretching from the Atlantic Ocean on its east coast to the Pacific Ocean on its west coast (see Figure 6.1). The 13 original states gained their independence from Britain in 1783 and the number of member states has risen to 50 in 1959 when Alaska and Hawaii joined the Union. The history of the mainland United States closely reflects its settlement which began on the east coast and spread across the nation during the 19th century, with the last two members of the contiguous mainland group of states, Arizona and New Mexico, joining the Union as recently as 1912.
