At the census of 1 December 1930, 4,077,099 residents lived in Switzerland. (present population; the resident was 4,066,400). In 1800 it is estimated that the population of Switzerland rose to 1,670,000 residents, in 1850, the year in which the first census was carried out, it was 2,392,740 residents, the following censuses assigned them respectively 2,507,170 residents. in 1860, 2,669,147 in 1870, 2,846,102 in 1880, 2,933,334 in 1888, 3,325,032 in 1900, 3,765,123 in 1910, 3,886,090 in 1920, 4,077,099 in 1930.

The growth of the population, very intense in the first half of the century. XIX, it decreased in the first decades of the second half, following the occurrence of a crisis in industry and agriculture. But here began towards the end of the century a period of fortunate economic expansion, which was accompanied by a very intense population growth, which lasted until the beginning of the world war (10.7 ‰ on average per year in 1888-1900, 12.5 ‰ in 1900-1910); this interrupts it, causing the exodus of many foreigners, nor does the growth resume, after the war, with the intensity of before. The population growth was not equally intense in the different regions of Switzerland: in general it was much stronger than elsewhere in the industrial districts. The cantons that recorded the greatest increase were those of Zurich, Geneva, Basel city and countryside, Solothurn, Neuchâtel, Zug. In some Alpine cantons (Appenzell, Uri, St. Gallen), however, the population has decreased.

The decrease in the percentage of growth in the last twenty years is due to the fact that, while on the one hand the influx of foreigners has decreased, which was instead very strong in the period 1890-1910 (in this period immigration exceeded emigration), the birth rate continued to decrease with ever more worrying intensity: it was on average 30.8 ‰ in the decade 1870-80, it remained around 2729 ‰ in the years from 1881 to 1900, but then it continued to decrease more and more: 21.2 ‰ in the years from 1910 to 1920, 18.4 ‰ in 1920-30; in 1934 it was 16.2%. It is true that mortality decreased significantly (23.5 ‰ in 1870-80; 16.9 ‰ in 1900-1910; 12.2 ‰ in 1920-30; in 1934, 11.3 ‰) which reached a value between the lowest in Europe: but in recent years this decrease has no longer been sufficient to compensate for the decrease in births. The surplus of births over the dead in the twenty years 1910-30 was only 6.3%; in 1934 it was 4.9 ‰ (in Italy 10.1 ‰).

The movements of emigration and immigration from outside have played an important part in determining the demographic physiognomy of Switzerland. Foreigners, attracted above all by the development of industries and trade, immigrated in large numbers especially in the last decades of the century. XIX and the beginning of the XX, but Switzerland also currently has a very high percentage of foreigners, the largest in Europe after Luxembourg; in 1850 there were 71,570, they rose to 150,907 in 1870, to 382,424 in 1900, and reached their maximum in 1910: 552,011 (147 ‰ of the total population); in 1920 there were 402,385, in 1930, 359,522. The most numerous are the Germans (1930: 134.561; 378.4 ‰ of foreigners living in Switzerland) and Italians (127.903; 357 ‰); followed by the French, Austrians, English, etc. Almost all of them are found in cities and industrial districts. The cantons with the highest percentage of foreigners are those of Geneva (303 ‰ of the total population: in the municipality of Geneva over ¼ of the population is made up of foreigners), Ticino (213 ‰), Basel (160 ‰).

The Swiss also emigrated in large numbers abroad. Statistics are available only for emigrants in overseas countries, the number of which has fluctuated a lot: it was on average 7600 per year in 1885-90; it dropped to less than 3000 in 1896-900; it remained between 4500-5000 in the fifteen years 1901-1915; dropped to 2950 in 1916-20, rose to 5880 in 1921-25, to 4650 in 1926-30; in recent years it has been very low (1220 in 1934). Overall, the Swiss established abroad are very numerous, especially in the countries bordering the mother country: in 1934 there were 312,375 of which 227,184 in Europe (France, Germany, Italy, etc.), 73,650 in America (United States, Argentina, etc.).

As for internal migrations, the number of residents living outside the communes and cantons of origin has increased more and more in the last decades, above all due to the attraction exercised by industry on the population of the countryside and mountains.

A demographic problem that has raised serious and justified alarm in Switzerland, where mountain territories are so extensive, is that of mountain depopulation. In some cantons it has truly taken on worrying proportions, with the partial or total abandonment of the highest mountain areas and the deterioration of crops and pastures. The causes are the same as those of other Alpine countries and are to be found in the difficult living conditions of the high mountains compared to the lower areas.

If the Swiss people do not constitute a nation in the proper sense of this word, it cannot be denied that it forms a solid unity by now, as demonstrated by the world war (war of nationality) which severely tested it: a tradition secular several times, the awareness of common interests, the certainty that only in the union each group can preserve its freedom, have formed a common “Swiss sentiment” very deeply felt by all the residents, despite the different nationalities to which they belong, and the freedoms that each canton is jealous guardian of. As for the division of the Swiss people according to the language spoken, in 1930 719 ‰ spoke German, 204 ‰ French, 60 ‰ Italian and 11 ‰ Ladino (Romansh); the rest (6 ‰) spoke other languages.