Did a colder climate trigger crises across the 17th-century world?

Possibly in part, but historians still disagree on whether there was a single crisis at all. In the mid-17th century, wars, revolts and collapsing states piled up: civil war in England, the Fronde in France, the climax of the Thirty Years' War, revolts against Spain in Portugal, Naples and Catalonia, and the fall of Ming China, the world's most populous state. In 2013 the historian Geoffrey Parker argued that this was a global 'General Crisis', made worse by the cooling known as the Little Ice Age. Others think it is a label stuck afterward on an unrelated pile of troubles.

The climate case is striking. Europe cooled by 1 to 2 °C, at the same time as the Maunder Minimum and big spates of volcanic eruptions, enough to cause crop failures on Europe's marginal farmland. Failed harvests pushed people into cities that could not sustain them, creating in some areas a Malthusian crisis. The 1640s saw more state breakdowns worldwide than any period before or since; no major state avoided war that decade, and over the century Poland saw only 27 years of peace, the Dutch Republic 14, France 11 and Spain just 3. Parker names war, climate change and migration as the main drivers of the century's population crisis.

The debate started earlier. In 1954, Eric Hobsbawm saw an economic crisis on the road to modernity; in 1959, Hugh Trevor-Roper coined 'General Crisis' for a clash between centralizing royal courts and the regional, land-based nobility. Critics push back. Niels Steensgaard noted that the Dutch Republic was enjoying its Golden Age at the very same time. Anthony Upton argued that revolts stayed local and sought customary rights rather than challenging kings: Portuguese rebels just wanted a different royal house, and the French princes leading the Fronde were horrified when England executed Charles I in 1649.