On 18 July 1936, various generals in the Spanish army rose up against the government of the Second Republic. The failure of the coup as it had been originally planned gave way to a civil conflict between the defenders of the democratic government and the backers of the military coup. Machado’s two Spains fought each other for nearly three years in a battle which reflected the political and social tensions affecting the world at that time.
The opposing armies were very different: on one hand, the Republican army possessed a limited number of professional soldiers and many popular militias belonging to political parties and labor unions. To this were added the International Brigades, formed from foreign volunteers of diverse origin; a fighting force which was highly motivated, but poorly coordinated and typically poorly organized. On the other hand, the Franco´s army had most of the professional military, along with Carlist and fascist militias, many native Moroccan troops, and the volunteers of the Condor Legion and the Corpo Trupe Voluntarie, sent by Hitler and Mussolini, respectively. (...)