This two-part series presents some of the most spectacular discoveries of modern climatic research. An international team comprising climatologists, historians and geologists has established that climate has played a crucial role in the development of historical events throughout central Europe. This applies, among other things, to the rise of the Roman Empire, the vast migration of peoples between 400 and 700 A.D., Hannibal's journey across the Alps, the persecution of witches in the Middle Ages, and the 30 Years War. This documentary presents the events in question and explains just how weather literally makes history.