Age of DiscoveryWar & Conflict Thirty Years' War 1618Major A devastating religious and political war kills perhaps a quarter to a third of the German population. ▲ MattersSaveShareTrace roots Longest chain: The Big Bang → First stars ignite → Supernovae seed heavy elements → The Sun forms → Earth forms → First oceans → First life → Photosynthesis evolves → Great Oxidation Event → Complex cells (eukaryotes) → Multicellular life → First animals → Cambrian Explosion → First vertebrates → Jawed fish → Fish walk onto land → The amniotic egg → The Great Dying → Dinosaurs appear → Asteroid ends the dinosaurs → Early primates → Apes split from monkeys → Human line splits from chimpanzees → Walking upright → First stone tools → Genus Homo appears → Homo erectus → Control of fire → First fired clay figures → First pottery → Potter's wheel → The wheel → Spoke-wheeled chariot → Hittite Empire → Iron Age begins → Rome founded (traditional date) → Roman Republic founded → Caesar crosses the Rubicon → Roman Empire begins → Jesus of Nazareth crucified → Paul spreads Christianity → Edict of Milan → Christianity becomes Rome's state religion → Carolingian minuscule → Gutenberg's printing press → Protestant Reformation → Thirty Years' War Community notesLoading notes… Learn more ranked by votesDocumentbritannica.comThirty Years' War (Britannica) ↗Editor's pickBookPeter H. WilsonEurope's Tragedy: A History of the Thirty Years War ↗Editor's pickBookC. V. WedgwoodThe Thirty Years War ↗Editor's pickVideoSearch on YouTubeThirty Years War history explained ↗Editor's pick