The Thirty Years' War was a series of conflicts that occurred in the period between 1618 and 1648 in the area of the Holy Roman Empire of the German Nation, but also in the neighboring regions of Europe. Historically, the war broke out almost 100 years after the Reformation on the territory of Germany and presents a series of conflicts between the European states. It was a conflict to acquire political influence and mastering territories in accordance with the interests of European royal houses that have been tried, after centuries of feudal fragmentation and disintegration, to demonstrate the power of the central government. In doing so, the religious differences between Catholics and Protestants served only as an excuse to start a war. The geographical and political aspects, armed conflicts during the Thirty Years' War resulted in changes of borders between European powers, created new alliances, formed new states and created a new order that has essentially shaped the geographical and historical mosaic of Europe in the next 150 years, and the years to come. The conventional classification of the Thirty Years’ War as a religious war overlooks the complex relations among European powers. During that war, besides the Catholic-Protestant military conflict, there were regular occurences of inside-Catholic (the war between the Habsburg, the Spanish and the French crown in northern Italy from 1628 to 1631) and intra-Protestant confrontations (the Danish-Swedish war from 1643 to 1645). Opposed Catholic-Protestant associations clashed in various stages as well (e.g. the participation of Catholic France as allies of the Protestant Sweden). The Thirty Years War is now considered an important part of European history, because at that time, it represented the first, almost "pan-European" escalation of the conflict between the majority of the European powers, the new way of war, a large number of victims and the creation of new geopolitical system of power in Europe.