During the nineteenth and twentieth centuries, France and Germany were Great Power rivals.  Their rivalry often led to conflict.  In the early nineteenth century, Napoleon led French armies through Germany repeatedly, dismantled the Holy Roman Empire, defeated the Austrians and Prussians, and was finally defeated by them in turn (most famously at the Battle of the Nations and (in part) by Blücher at the Battle of Waterloo).  Sixty years later France was defeated by Prussia in the Franco-Prussian War and lost Alsace and Lorraine.  Forty years after that only the Miracle of the Marne saved France from another German occupation of Paris, although it did not prevent four years of trench warfare on French soil.  Finally, in 1940 there was no miracle to save the French from German attack and occupation (although there was at least one miraculous operation during those dark days).   Part of the background to the Franco-German rivalry and tension during this time was the demographic trends of both countries.  In 1800, France had a population of 30 million, twice that of Germany (based upon current borders).    But by 1939 and on the eve of the war which was to prove a disaster for France, Germany had a population of 60 million, around 50% higher than France’s population of 41 million.  According to the French National Institute of Demographic Studies (INED) recent study on the demography of the two countries, this demographic reversal had a major impact on their shared history:

"One consequence of the early fertility decline was slower French population growth in the 19th century compared with its European neighbours, and early population ageing ... The crushing defeat in the Franco-Prussian War of 1870-71 was attributed to the superiority of the Prussian education system, but also to the demographic decline of France which was believed to have lost its triumphant vigour of the Napoleonic First Empire. Similar reasons were given to explain France's vulnerability in the face of its German enemy at the start of the First World War. These ideas served to justify the introduction of pronatalist policies at the end of the 19th century."

“German growth was due to a surplus of births over deaths, with a birth rate that remained consistently above the death rate throughout the nineteenth and early 20th centuries (discounting war years),” observed Pison [the INED research director]. “By contrast, the curves of births and deaths in France remained very close over this same period, and the resulting low level of natural growth was even cancelled out by the losses of the 1914-1918 war. It was only thanks to immigration that the population did not totally stagnate between 1900 and 1939."

Beginning at the end of the 19th century, France saw a strong influx of immigrants, rising notably in the years immediately after World War I. "Germany, on the other hand, far from being a country of immigration, saw an exodus of its inhabitants towards the New World," Pison underlined. "Without this emigration, its population would have increased even further. However, the demographic position looks set to change once again. According to the UN’s medium population projection, France is set to reach Germany’s population in about 40 years as its population slowly increases and Germany’s decreases.  This reversal has been a long time coming – since the end of World War Two Germany has had on average half a child less per woman than France.  As the study notes:

“This gap may seem small, but in demography it is substantial, especially if it persists for decades...If fertility remains low, a constant inflow of migrants will be needed to offset the surplus of deaths over births and to maintain the German population at its current level. Unless, that is, Germany resigns itself to the prospect of steady population decline”

For years French policymakers felt that the demographic numbers were against them when they looked to their eastern neighbour.  Now it seems as if the situation is changing and Germany’s demographic dominance of the continent will end in the coming decades.  Having said that, a few decades is a long time and predictions over that time period are fraught with difficulties…after all, a few decades ago we were worried about imminent mass global starvation due to overpopulation. Thankfully we’ve moved on since then (wait a minute...)