Population density shows marked differences and variations over time. Its ‘center of gravity’ is constantly shifting towards the West and recently also towards the S: the increase in population in the Atlantic region is always lower than that recorded in the Pacific and towards the Gulf of Mexico. Overall, however, the densities of the Atlantic region remain higher; the values decrease towards the Mississippi and, even more rapidly, towards the Rocky Mountains, down to the lows of the internal plateaus; beyond, the densities rise again towards the Pacific coast, without reaching, however, not even one third of the values of the central Atlantic coastal region. States in which the population exceeds 100. per km2 they are all on the Atlantic coast, including Florida, plus Ohio. However, the most populous state is California (36.5 million), followed at a distance by Texas (23.9), New York State (19.3) and Florida (18.3), which in recent decades has recorded an exceptional increase, due to the immigration of adults (retirees) from other states. At the opposite extreme is Alaska, which is the largest state (1,530,700 km2), but the least populous (about 680,000 residents); more significant, however, is the case of Montana and Wyoming, at latitudes corresponding to that of but the least populous (about 680,000 residents); more significant, however, is the case of Montana and Wyoming, at latitudes corresponding to that of but the least populous (about 680,000 residents); more significant, however, is the case of Montana and Wyoming, at latitudes corresponding to that of Central France, where a total of about 1,500,000 people live on an area more than double that of Italy, less than 3 residents / km2.
The US population is among the most urbanized in the world, considering that about four fifths live in cities with at least 100,000 residents. Urban growth has been continuous, even if in the most recent decades it has shown a tendency to favor the more peripheral areas over the consolidated city centers. Consequently, it is difficult to establish the exact amount of the population of an urban center, to which various peripheral crowns must be added even if at a great distance and beyond administrative or state limits. New York, with its metropolitan area which also extends into neighboring states, exceeds 18.8 million; not far away, the Philadelphia metropolitan area exceeded 5.8. Further south, the Washington metropolitan area (5.3 million) overflows from the federal district and constitutes the southernmost sector of the so-called Megalopolis which extends NW as far as Boston (4.5 million), also including the metropolitan area of Philadelphia, for a total of about 45 million residents. AS, the major urban center has become Atlanta, the capital of Georgia within a few decades, with over 5 million residents. In Florida, large coastal aggregates stand out, including Miami-Fort Lauderdale (5.5 million residents) and Tampa-Saint Petersburg-Clearwater (2.7).
● New York, the most populous city at the time of the declaration of independence, with fewer than 80,000 residents at the first census of the country (1790), it exceeded 100,000 in 1820, rose to nearly 700,000 in 1850, approached 3.5 million at the end of the century, and in 1930 it had recorded a further doubling in the center, while in the metropolitan area it they exceeded 10 million: even then the built-up urban areas largely exceeded the administrative limits established a few decades earlier, when the settlements were much more limited in size. In the particular case, New York even overflowed the state, invading neighboring New Jersey. Other cases of large cities with rapid growth are those of Chicago (from 30,000 in 1850 to 1,700,000 in 1900) and Los Angeles (from 100,000 in 1900 to over 2,300,000, for the metropolitan area, in 1930).
● The oldest cities are those of the Atlantic sector and the Great Lakes, which began to be structured in the 19th century. and all of which are multiracial in composition, typically including Europeans, Africans and Asians. Since the end of the 19th century, industrial settlements and workers’ residences have developed around the downtown (the central nucleus of the city); with the development of transport, the wealthy classes moved to external residential areas, into single-family houses. In the central parts more and more skyscrapers have been built, and of ever increasing height, where there are banks, headquarters of industries, department stores, public administrative structures, or rather the few businesses capable of paying high rents. Two categories of buildings survive around the skyscrapers: some whose low height is now a symbol of prestige, as it indicates that the owner does not need to make the most of the land; others completely dilapidated, populated by outcasts of all kinds, who pay low rents, while the owners wait to be able to tear down and build a new skyscraper. as it indicates that the owner does not need to make the most of the soil; others completely dilapidated, populated by outcasts of all kinds, who pay low rents, while the owners wait to be able to tear down and build a new skyscraper. as it indicates that the owner does not need to make the most of the soil; others completely dilapidated, populated by outcasts of all kinds, who pay low rents, while the owners wait to be able to tear down and build a new skyscraper.
The South Atlantic, with a total population of nearly 58 million, is the most populous of the major regions, with a much higher than average growth rate; immediately thereafter follows the southern Pacific coast, with 48.7 million. In short, the preference of the US population for the coastal strips is evident.
● In the central regions, between the Rocky Mountains and Appalachia, densities drop. Among the cities here stand out Chicago (9.5 million residents) and Detroit (4.5), while Minneapolis-Saint Paul reaches 3.5 million, and Cincinnati, Cleveland and Kansas City have about 2 million; further to the South, Houston it has 5.5 million citizens, the Dallas-Forth Worth agglomeration about 6 million, that of Saint-Louis 2.8. The northern and southern borders of the various states of the large central region (Mid; west) often rest on parallels: these are administrative limits decided in Washington before the populating of the ‘West’ by Europeans; the ‘territories’, placed under direct federal management, could apply to be qualified as states only when the taxable population had exceeded the threshold beyond which a local administration could be considered self-sufficient.
● In the region further to the West, that of the Rocky Mountains, we find the lowest densities in the USA (excluding Alaska), with an average of 10 residents/km2. Here the western and eastern borders between states also rest on the geographical network, so much so that Colorado and Wyoming have quadrangular shapes. Sparse settlement is occasional and urban centers to the north are also limited in size; to the South, the major cities concentrate a large part of the population of their respective states: Phoenix(4 million residents) is home to nearly two thirds of the population of Arizona; here and in Nevada, however, the recent increase has been very strong.
● On the Pacific coast, finally, the average density increases again, up to 89 residents / km2 in California. AN, the Seattle-Tacoma agglomeration reaches 3.3 million residents; but in the heart of California, San Francisco exceeds 7 million and the urban formation gravitating to Los Angeles, with over 17.8 million, is among the most impressive in the world. In the two concentrations live over two thirds of the residents of the most populous state. California also experienced strong immigration from all other states, and therefore an increase much higher than the national average.
In the USA, the mobility of people is much more accentuated than in Europe: it is common for young people to complete higher education without living in the family, moving to the university, often in another state; and, later on, finding work by changing residence again is in the order of things. People used to go W because the region was depopulated; today because job prospects are better in the Pacific than in the Atlantic. Therefore, people of working age migrate, so much so that the population of the NE is on average older than that of the Western states. The destination of migrants is generally an urban area. In the USA, given the lack of a pre-existing population, the settlement was centralized from the beginning: it was not the product of immigration from the countryside, depopulated, but of the influx of people from outside the continent. Its growth, therefore, immediately presented itself in an exasperated form.
There is no official religion; according to the data calculated by the individual confessions, there would be about 25% of Protestants, 22% of Catholics, 34% of other Christians (there is a strong tendency towards the establishment of religious sects), 10% of non-believers, about 2% of Orthodox and as many Jews, less than 2% of Muslims, etc.