The Thirty Years' War lasted from 1618 to 1648 in Europe, and was one of the most destructive wars in European history, claiming around eight million lives in total. In some places half the pre-war population died and the war thoroughly influenced the Baroque Era which had prevalent themes of "vanitas" or the ultimate death and decay of all earthly things.
The war was linked to preceding and subsequent conflicts, and in the Netherlands it is known as the Eighty Years' War ending in 1648 with Dutch independence being recognized de jure.
The war has its roots in the Protestant Reformation, where especially northern Europe became Protestants, and broke away from the Catholic church. The Protestant nobles in Bohemia rebelled against the Holy Roman Empire, which was Catholic, and ruled by the King of Austria of the House of Habsburg. While the Habsburg states included the global Spanish Empire, the anti-Habsburg alliance came to include Protestant nations such as the Netherlands and Sweden, as well as Catholic France.
The war ended in 1648 with the Treaty of Westphalia (signed and negotiated in both Münster and Osnabrück) which established the concept of Westphalian sovereignty, the foundation of modern international relations. The basic concept is that all states would be legally equal, and should not interfere in each others' domestic affairs. As war between European neighbours became the exception rather than the rule, travel was less of a danger, allowing a tradition of young noblemen to go on a Grand Tour across the continent.
This principle was an end to the Holy Roman Emperor's political influence; the title became purely ceremonial, until it was abolished in 1806. While Austria became a great power in its own right, Spain lost its role as a dominant power in Europe.
The Netherlands rose as a sovereign nation, experiencing the Dutch Golden Age after the war. Sweden annexed much of northern Germany, and nearly came to encircle the Baltic Sea. The Swedish dominance of the Baltic would last a century and end after the Great Northern War.
The war had a huge human toll, in Europe comparable only to the two World Wars; in some regions nearly half the population died due to the near constant fighting, plundering and diseases spread by the moving armies. Works of fiction set or written during this era often paint a grisly picture of the - very real - atrocities committed during the war and the bleak lot of both the common soldier and regular civilians just trying to scrape by.
- Lützen, Germany - the place where Gustav II Adolph of Sweden, died in battle elevating him from a mere mortal to a martyr for the Protestant cause and a hero for Lutherans all over Europe
- Rothenburg ob der Tauber, an old town in Franconia - to this day a story of how the town was spared destruction in the war is reenacted
- The Vasa Museum (Stockholm/Djurgården), Sweden: The Vasa is a 64-gun galleon built for the Thirty Years' War, which sank in the Stockholm harbour in 1628, a few hours into its maiden voyage. Salvaged in 1961, it is the only preserved vessel of its kind.
- Magdeburg was sacked and almost entirely destroyed in an act of war so brutal even contemporary Catholics expressed outrage at the deed of their coreligionists
- Vienna has the Heeresgeschichtliche Museum that has several high profile exhibits from the war, including the bloodstained order of Wallenstein to Pappenheim to intervene in the battle of Lützen where the latter would die (leading to the bloodstains)
- Münster's townhall is the place where the Treaty of Westphalia was signed in 1648