The financial crisis has given rise to several historical comparisons, not least the Great Depression. I would like to invoke another for the eurozone crisis – the 30 years war, which ravaged central Europe from 1618 to 1648.

Both the eurozone crisis and that terrible war occurred amid sudden power shifts; they were triggered by seemly trivial events; and they became incredibly complicated. They are also marked by sudden regional power shifts. Before 1618, the Holy Roman Empire was almost equally divided into Catholic and Protestant electorates. The truce ended when the balance of power shifted with the ascension in 1617 of the Catholic Ferdinand as king of Bohemia, who was one of the seven electors of the emperor. The actual war started a year later when rebels threw some of the king’s advisers out of a window. The famous defenestration of Prague triggered the first battles of a war between Protestants and Catholics, which went completely out of control. The war had four phases, and drew in outside nations – the Danes, the Swedes and finally the French.

The eurozone, too, has been subject to an internal power shift in the past five years, with the relative rise of German economic power. The eurozone crisis also had a comparatively trivial trigger, a fiscal meltdown of a small country at its outer perimeter. This too unleashed a wider economic conflict between a largely Protestant north and a Catholic/Orthodox south. When the eurozone’s modern rulers assembled in Brussels this month to sign the modern equivalent of a peace treaty, they were interrupted by the cross-current of a much older conflict – a UK-versus-the-rest dispute. So instead of one peace treaty, they ended up with two overlapping and interacting conflicts. Europe is once again getting absurdly complicated.