A brief examination of the essential features of the population of Great Britain as a whole must be added to that of its relief and climate to complete the setting for the more detailed study of its parts. No area can be considered as a separate entity, each is an integral part of the island whole.
Diversity within unity is one characteristic of the population pattern. The variety of relief that is contained within the unity of the island form, the variability of the weather within the equability of the oceanic climate, these are paralleled by the diversity of the economy and society within the uniformity of this densely peopled and highly industrialized land. Some 80 % of Britain's inhabitants live in towns, and nearly half of these in Greater London and the six provincial conurbations. The British are shopkeepers and office workers, miners and factory workers; only one man in every two dozen farms the land. But such figures give a wholly false impression of uniformity. There can be few greater contrasts within so small an area than between some highland parishes of Scotland, northern England or Wales inhabited by two or three hundred folk, and the streets of Glasgow, Birmingham or London with their thronging thousands.
Change within stability is a second key note. Within the span of man's occupation of the land, the patterns of relief and climate remain in broad essentials stable; what alters is human knowledge and evaluation of them. Efforts to use the opportunities of the physical environment well and to overcome the limitations effectively bring about change now slow, now rapid, and often albeit painful, in the patterns of population. There is change in the total numbers: a great increase, though at varying rates and not an uninterrupted one, has taken place since the time of the Domesday Survey. The information collected by the Domesday Commissioners in 1086 suggests that about 2 m. people lived then in Britain to the south of the Ribble and the Tees. A slow increase, with perhaps a marked fall as a result of famine, pestilence and war in the later fourteenth and early fifteenth centuries, brought the total to some 5½m. in England and Wales and 1 m. in Scotland when Gregory King made his estimate at the end of the seventeenth century. The later eighteenth century and the nineteenth century was a period of rapid increase; the birth-rate remained high at about 34 until the 1870's, the death-rate fell steadily and population rose to 8.8 m. in 1801, 27.3 m. in 1851 and 43 m. in 1911, a fourfold increase within the nineteenth century.
There is change in the population pattern between country and town: in England 80 % of the population in 1770 was rural; in 1850 the balance between town and country was even; by 1931 only 20% of the population is recorded in rural districts. It is estimated that during the nineteenth century some 25 m. people left Britain to settle in Europe, America and the Colonies. This number includes foreigners who sailed from British ports and also British who returned later, and is offset in part by immigrants into Britain, but since 1871 the net loss by migration has been about 3½ m.
Within the island the pattern of distribution of population densities shows both stability and change: throughout, the highland areas have been sparsely and unevenly peopled, with large areas empty; throughout, the fat agricultural lowlands have been well populated with many villages evenly spaced. But since the industrial revolution, dense urban populations, in many areas over 1,000 per square mile, have grown upon the coalfields; today, there are trends, sufficiently well established, to suggest that the old industrial and urban concentrations are weakening, that modern industry is becoming more widely distributed, and thus a new pattern, or rather the revival of an older one, with the centre of gravity of the population to be found in the Midlands, somewhere approximately in the middle of the belt of country stretching from the Wash to the Severn, is becoming reestablished.