There is no simple explanation for why the Early 20th Century was so catastrophic for the World System: World War I (WWI), the Great Depression (GD) and World War II (WWII), all in a row, all followed by a series of minor wars, crises and unresolved problems until the Present.
Imagine that you were British inventor, physicist and engineer Archibald Montgomery Low (1888-1956) and you had heard about George Vacher de Lapoguepredictions about growth and catastrophe in the 20th Century, but you found them a little wacky.** So you produced the graphic above (based on mental models, mathematical equations and speculation) predicting the path of British Development for the first half of the 20th Century to check de Lapoque's predictions. Each Attractor Path was based on a different Geopolitical Alignment:
Historiography of the causes of World War I Historians writing about the origins of World War I have differed over the relative emphasis they place upon the factors involved. Changes in historical arguments over time are in part related to the delayed availability of classified historical archives.
Schroeder, Paul W. Stealing Horses to Great Applause: The Origins of the First World War Reconsidered (2025), influential essays by a leading historian
Timeline of the Great DepressionThe initial economic collapse which resulted in the Great Depression can be divided into two parts: 1929 to mid-1931, and then mid-1931 to 1933. The initial decline lasted from mid-1929 to mid-1931.
Three component state variables of the UKL19 Model explain 100% of the Variation in the indicators: UK1 = (Overall Growth), UK2 = (XREAL+X-L-HOURS-U) Export-Employment Controller and UK3 = (X-XREAL-Q-N) Malthusian Export-Price Controller.
UKL19 Time Plot
Overall growth in the UKL19 model continued through the Nineteenth Century and may or may not have been approaching a steady state around 1900. The Export-Employment and Malthusian Export-Price Controllers hit a minimum just before 1860 (see the Boiler Plate for a discussion of Historical Growth Controllers).
The possible victory of Germany in World War II (WWII) is the standard counterfactual for the Long Nineteenth Century (see the Notes below and the video above). Although interesting, I'm not sure it's the bestcounterfactual, at least from the standpoint of World-Systems Theory (WST).
From the WST perspective a more interesting counterfactual is "What If WWI, the Great Depression and WWII had never happened". What would the history of Long Twentieth Century have been?
If we have systems models of the major countries in both the 19th and 20th Centuries, we can forecast the 19th Century models into the 20th Century to create an alternative history where WWI, the Great Depression and WWII never happened. When then compare the actual paths of the comparable 20th Century models to see what was actually different.
One possible problem is that the data for the 19th Century, the War and Inter-War Periods are not great for most countries in the World-System. However, what we can do is focus on the estimated Systems Models which do show variability across the major countries over the time period (0-2000+, see examples here).
In future posts, I will start with the World System (WL19 and WE20) and then go on to the other major countries in the Long Nineteenth and Twentieth Centuries (Germany, the UK, France, the US, Italy, Japan, Russia, etc.).
I have already started with some countries, for example France as an example (here). From the FRL19 model, it turns out that the Great Depression and possibly the collapse during WWI can be predicted in France from 19th Century data. The same is not the case for the DEL19D Model (Pasdirtz, 1981).
Historiography of the causes of World War I Historians writing about the origins of World War I have differed over the relative emphasis they place upon the factors involved. Changes in historical arguments over time are in part related to the delayed availability of classified historical archives.
Schroeder, Paul W. Stealing Horses to Great Applause: The Origins of the First World War Reconsidered (2025), influential essays by a leading historian
Timeline of the Great DepressionThe initial economic collapse which resulted in the Great Depression can be divided into two parts: 1929 to mid-1931, and then mid-1931 to 1933. The initial decline lasted from mid-1929 to mid-1931.
Dec 24, 2025. The New York Times is reporting (here) that "for the second consecutive year ...[France has failed]... to agree to a new national budget by the end of the legislative calendar." It is difficult to understand what is going on in France without some historical background, specifically how France responded to World War I and the Great Depression. ChatGPT reports that
In this post, I am going to use France's economic statistics in the Long 19th Century to forecast France's economic performance in the early 20th Century. The multi-model forecasts based on different input assumptions for the FR19 Model are presented in the graphic at the beginning of this post. The results are somewhat surprising!
I looked at the following possible drivers for the French Economy: (1) None (Business-as-Usual, BAU, and Random Walk, RW), (2) Technical Productivity, TECHP, (3) the World System (W), (4) Western Europe (WE), (4) Germany (DE) and the United States (US). The best model, using the Akaike Information Criterion was US input ([-1215 < AIC = -1138 < -1077]). All the models were unstable (some were cyclical, see the Eigenvalues below in the Notes with the AIC Statistics) and collapsed (except the RW) at some point in the Early 20th Century.
At first, you might think that the models are predicting the Great Depression. They are not!** We know from the historical record that the French Economy did not collapse as a result of shocks from WWI, the Great Depression and WWII (according to ChatGPT, in any event).
Then, how are we to understand the forecasts from the 19th Century Models? To understand the French Economy in the 19th and early 20th Century, we have to look back further before the first (1878-79) and the second (1848) French Revolutions. I'll do that in future posts.
For this post, let's take the German perspective as embodied in the Schlieffen Plan to invade and neutralize France before the First World War. Assume (counterfactually) that Field Marshall Alfred von Schlieffen had output from the FR19 BAU model (here) or at least understood that France was a collapsing power. The idea of a lightning first strike to neutralize France before fighting Russia on the Eastern front would seem attractive and necessary.
Of course, everything changed for France after WWI, during the Inter-War Years. France reacted very conservatively to the Great Depression and stabilized the economy (or at least turned it into a Random Walk).
Returning the present Budgetary Crisis in France, it would be reasonable to predict that any fundamental changes would require formation of a New Republic (see history here). A budget crisis is, historically, not significant enough to trigger major political change.
You can stabilize the FR19 BAU model with instructions in the code (here). For more information about data sources and how the models were constructed, see the Boiler Plate. You can follow a Blog Roll of other postings I have done on the French Economy here.
Notes
** This may be too fine a point. The FR19 Model is characterizing the French Economy as in Growth-and-Collapse mode after 1900. And, Growth-and-Collapse was certainly a factor as\s France faced WWI, the Great Depression and WWII. The historical events of the early 20th Century, however, are more complicated than the state of the French economy. There is no simple monocausal explanation.
Three components from the FR19 BAU modelexplain almost 100% of the variance in the indicator variables. The components are (1) FR1=(Overall Growth), (2) FR2=(0.5633 Q + 0.5979 X - 0.2781 N - 0.4070 HOURS) Malthusian Export Employment Controller, and (3) FR3=(0.75876 XREAL - 0.3849 X - 0.4924 HOURS) Export-Price Employment Controller.
FR19 System Matrix
The FR19 BAU System matrix is unstable with two strong negative feedback components, F[1,3] = -0.05130896 and F[2,3] = -0.05297408, both from the Export-Price Employment Controller (recall that World Trade Collapsed during the InterWar years).
In an earlier post (here) I investigated whether Latin America, in the 19th Century, benefited from the Monroe Doctrine. As a Geopolitical Alliance, Latin America benefited slightly from US intervention up to the 1880s, but not after that. However, the Monroe Doctrine was designed to minimize European influence in Latin America. One way to operationalize "interference" is to ask how the LA_19_US_input model handled shocks compared to the LA_19_WE_input.
In the 19th Century, interference in Latin America from Western Europe, the UK and the US is best viewed as aRandom Walk.
A one standard deviation shock LA Growth (LA1) had effects extending out over about a half decade (see the graphic above). However, the Western European shocks were initially negative, meaning that growth in Western Europe depressed Latin American Growth. All the effects are small compared to the size of the shock.
In fact, the AIC statistics above shows that Growth Shocks are best viewed as a Random Walk. For comparison, the three models are presented below.