Thirty Years War (1618-1648)

The Thirty Years War devastated Central Europe with unprecedented brutality, killing approximately 8 million people — a third of the German states' population — which is 60% more deaths than the Napoleonic Wars inflicted. The Peace of Westphalia (1648) established state sovereignty and non-interference, creating the modern nation-state system still governing global politics. Its death toll as a share of population (roughly a third) stands as a benchmark for demographic catastrophe.