The last revolutionary process of the era, and the only one initiated in the middle of the interwar period, opened in Spain in 1931. It was unique in not having been stimulated or catalyzed by major war; it was almost exclusively the product of endogenous factors, which to that extent makes it the most singular of all the European cases under consideration. This was all the more extraordinary in that Spain had an entire century of parliamentary government behind it, even with all the limitations involved in early parliamentary development. For the second half of that period, stable and reformist constitutional monarchy had prevailed, free from any significant foreign or military pressures in Europe, complicated only toward the end by the establishment of the Spanish Protectorate in northern Morocco in 1913.