With the U.K. on its way out of the European Union, now seems like the time to ask!
I am not talking about 1989. Rather, I am talking about 1871. Did the emergence of a unified German nation state owe itself to British policy?
In an entertaining tour-de-force, Thilo Huning and Nikolaus Wolf of Humboldt University argue yes, yes it did! The inituition is fairly simple. In 1815, the U.K. pressured Prussia into accepting large territories in western Germany rather than Saxony. That gave Prussia sway over the large river systems than carried German commerce. When the Zollverein came along, many of the smaller German states joined because there was not really much of a cost: Prussia controlled most of their commerce anyway. So by 1835 you had the Zollverein and (eventually) a unified German Empire.
But what if the Prussians had got their way and annexed Saxony instead of Westphalia? Well, the authors construct a series of low-cost trade routes and measure how much joining the customs union would have benefited the various German states. They then measure how much control Prussia had over the state’s commerce anyway. They find that the tradeoff predicts the decision to join the Zollverein pretty well: the less control a state had to lose, the more likely it was to join.
They then run the model using a hypothetical Prussia that controls Saxony but has no western territories. They find that no state south of the Main would have had incentives to join. Zollverein expansion peters out in the early 1830s with a map including only the blue-shaded areas below:
How would later German history have been different?