a series of European wars (1618-48) on political and religious issues, fought orig. between German Catholics and German Protestants, but later involving the Swedish, French, and Spanish
See Thirty Years' War in American Heritage Dictionary 4
noun
A series of wars in central Europe beginning in 1618 that stemmed from conflict between Protestants and Catholics and political struggles between the Holy Roman Empire and other powers. It ended with the Peace of Westphalia (1648).