Von Mayr believes the war had a depressing influence upon the rate apart from the mere absence of the men, as shown in the fact that immediately upon the cessation of hostilities it recovered in Bavaria, although it was several months before the return of the troops.
Mayo-Smith, in remarking on the influence of war on the marriage-rate, says that in 1866 the Prussian rate fell from 18.2 to 15.6, while the Austrian rate fell from 15.5 to 13.0.In the war of 1870-71 the Prussian rate fell from 17.9 in 1869 to 14.9 in 1870 and 15.9 in 1871; but in the two years after peace was made it rose to 20.6 and 20.2, the highest rates ever recorded.

In France the rate fell from 16.5 to 12.1 and 14.4, and then rose to 19.5 and 17.7, the highest rates ever recorded in France.
Influence of Rural and Urban Life .-- Rural districts are always very prolific, and when we hear the wails of writers on "Social Economy," bemoaning the small birth-rates of their large cities, we need have no fear for urban extinction, as emigration from the country by many ambitious sons and daughters, to avail themselves of the superior advantages that the city offers, will not only keep up but to a certain point increase the population, until the reaction of overcrowding, following the self-regulating law of compensation, starts a return emigration.
The effect of climate and race on prolificity, though much spoken of, is not so great a factor as supposed.

The inhabitants of Great Britain are surpassed by none in the point of prolificity; yet their location is quite northern.

The Swedes have always been noted for their fecundity.

Olaf Rudbeck says that from 8 to 12 was the usual family number, and some ran as high as 25 or 30.