Azaña had banished Franco in Morocco, who in October 1934 had greatly influenced the struggle against the revolution by the Ministry of War. Thoughtful of the fate of his country upset by relentless social hatreds, the general decided to join the struggle to put an end to the frenetic activity of the left, and to rebuild the nation on the basis of a happy marriage of new and ancient values. He had constituted the foreign legion, the Ternius, in the Riff, and a nucleus of 2 thousand Moors decided on everything. After February 1936, Franco had made contact with Antonio Primo de Rivera, with the divisionari of all the Riff, with those of the garrisons of Cadiz, Seville, Cordova, Barcelona, ​​Zaragoza, Pamplona and especially of Madrid to agree on the insurrectionary movement. On the afternoon of July 17, the African army rebelled; within 48 hours the revolt broke out in almost all the major centers of the metropolis.

According to sourcemakeup, Franco wants to cross the Strait of Gibraltar to feed the insurrection in the peninsula with his fierce forces. But the fleet in its majority takes the side of the government and stands there on the strait to block its way. The movement would have been condemned to failure if the first legionary aviation departments had not caused the overthrow of the forces with their intervention. Thus began the real war operations in the metropolitan territory. The government relies on army forces and popular militias: but the army was crumbled by the government itself with its five-year policy of suspicion and misunderstanding, Franco’s motion then ended up upsetting the remains of the old army of Spain; the popular militias lack discipline and instruction. Franco’s troops have the same drawbacks as the adversary; lack of cohesion and training. On the other hand, however, they have a greater number of career officers which increase their performance. The target of the insurgents is Madrid, and in fact they are moving concentrically to reach it. A great arch is outlined resting on Burgos, Salamanca, Badajoz, Seville that tightens around the capital. The march is facilitated by the fact that the insurgents follow the directions of the rivers, avoiding the natural barriers of the sierras. In a few days some columns have traveled 250 kilometers: Madrid is about to fall and the whole campaign is about to end. But this time the influx of foreign officers and volunteers alongside the reds with modern material restores the balance. The war of movement is over, the trench war is now tightening all around Madrid. Until the spring of 1936 nothing decisive around the capital: every attack, after an initial success, was rejected, every advance contained, every flaw quickly repaired. Having thus blocked the Madrid front, the nationals, received in turn reinforcements of volunteers and means, managed to provoke a material and moral imbalance in the sector of Malaga which led to the war of movement (February 5-8, 1936). The objectives to be achieved are remarkable: to occupy the entire Spanish coast parallel to that of Morocco, already in the possession of Franco, to control the bottleneck of the western gate of the Mediterranean, exploit the logistical value of the port of Malaga through which it is possible to refuel the nationals from the Mediterranean as well as the Atlantic, take advantage of the moral effectiveness of the conquest. The legionaries, with the help of national troops, attack on three concentric columns marching on Malaga. Attacking forces superior in morale, military doctrine, training, discipline, and material power, achieve success by achieving predetermined goals. On the Castilian front, which has been stabilized for some time, it was decided to undertake an action far more important than that of Malaga. To this end, a concentration of forces is carried out in the Madrid sector, whose investment is decided (8-12 March) with the aim of reaching Guadalajara, and then take the red side backwards. “The Italian legionaries… in the first days overwhelmed all the red defenses, stormed one position after another, literally rolled” departments and battalions of militiamen, the advance reached a depth of 40 kilometers…: the avant-gardes settled around Guadalajara “. But the weather conditions, adverse to the nationals and favorable to the reds, allowed them to use the aviation, making it difficult for the legionaries to advance despite their valor. battle, made particularly hard by the setbacks mentioned above, the command, to spare the troops already so tried, “at a certain point gave the order… to retreat and this was a big mistake”.

After Guadalajara there was nothing advantageous to try on the main theater, and the action against Cantabrian Spain was decided. Guadalajara thus becomes the distributive symmetry axis of military operations in 1937. In fact, before Guadalajara we have, agile and decisive, the action of Malaga, then the Basque-Asturian one. There were two red Spains to fight: the “major” or Mediterranean, the “minor” or Cantabrian. When the decisive action in the main sector failed, that of the north appeared in the general economy of the war as the most favorable to the activity of the nationals. The principle of beating the opposing forces separately was imposed. In addition, the Basque-Santander front presented marked characteristics of the least resistance point of the opposing line-up: inferiority in personnel and armaments, especially in artillery, almost complete lack of aviation, difficulty in obtaining material and human aid; the only red advantage is the difficulty of the terrain. The economic and military objectives of the Cantabrian action are noteworthy. Franco, unlike the reds, had a lot of copper but little coal and iron; these metals were largely found in the north. The war economy required taking possession of those practically unlimited mineral resources, which also offered a means of pressure on Britain engaged in rearmament. Militarily, then, once the northern front was eliminated, a progressively threatening danger for the side of national Spain would have been removed, and such a sum of forces would also be made available to the latter to achieve the final victory against Valencia and Barcelona. Thus the Cantabrian campaign would have prepared the victory in the Mediterranean over the Atlantic. Finally, once the Basque-Asturian provinces were eliminated, the national fleet could have operated together in the Latin sea. Cantabrian red Spain looks like a rectangular enclave with an average depth, on the short side, of 50 kilometers from the sea. The greatest obstacle to overcome was the terrain, that is the Cantabrian mountain range, which has always opposed the imperviousness of its watershed and the labyrinth of its transverse buttresses to every invader. But an army of high value and equipped with modern means of attack and traction like the national one, operating concurrently in the sense of meridians and parallels, sooner or later had to overcome this inviolate plateau from the Roman conquest to today. Military mishaps in situ, namely the siege of Bilbao (whose “ iron belt “was found more equipped than previously believed, preventing the achievement of a quick victory after the brilliant initial success), and the deviation suffered due to the red attack of Brunete (for which, to restore the equilibrium, made it necessary to move large forces from the north and all en masse the legionary aviation), delayed the Cantabrian action which, beyond the expected, took place from the end of March to the end of October. The fall of Gijón completes the asphyxiation of Asturias, marking together with the collapse of the northern front.