thirty years' war

noun

1. the war, often regarded as a series of wars (1618–48), in central Europe, initially involving a conflict between German Protestants and Catholics and later including political rivalries with France, Sweden, and Denmark opposing the Holy Roman Empire and Spain.

noun

1. a major conflict involving principally Austria, Denmark, France, Holland, the German states, Spain, and Sweden, that devastated central Europe, esp large areas of Germany (1618–48). It began as a war between Protestants and Catholics but was gradually transformed into a struggle to determine whether the German emperor could assert more than nominal authority over his princely vassals. The Peace of Westphalia gave the German states their sovereignty and the right of religious toleration and confirmed French ascendancy

A war waged in the early seventeenth century that involved France, Spain, Sweden, Denmark, Austria, and numerous states of Germany. The causes of the war were rooted in national rivalries and in conflict between Roman Catholics and Protestants. For all the bloodshed, there was no decisive winner or loser. The Peace of Westphalia, which ended the war in 1648, did affirm, however, that the German states could be Catholic or Protestant at the choice of their rulers.