Francoist State Republicans

Fruitless Madrid outlet provided an important lesson to Franco for the future of war: continuing with the capture of a well defended city as the capital of the nation, seemed not very sensible. Best thing then was cementing his power especially in the North of the country, which would give him the chance to complete the fence that was preparing for some time. The high national command, decided to finish with the last Republican hotbeds in the northern provinces, focused its attention on the conquest of Bilbao, Santander and mainly Asturias, where Republicans had made strong. On March 31, 1937 began the offensive. The nationalists put best of its offensive operation. If they could assure the North, would hands be them free to regroup their forces around Madrid. Preparations for the expedition of the North were made with meticulousness.

Franco relied on its division of elite (Navarra division) composed of 4 brigades with 18,000 men. At the same time, he received the help of the arrows Brigade Black, battalion composed of 8,000 Spaniards commanded by Italian officers. The air domain was guaranteed by Italian and German; aircraft and the blockade by sea by the national squad with the Canary Islands cruise to the front. The conquest of the North would be supervised by the general Llano de la Encomienda, who as a first task, had for mission make the conquest of the Basque country (Northern Spain, border with France). Thus began the famous campaign of Biscay. Republicans, whose possessions outside the Spanish Center nearby of a thread, had tried to regroup while Franco attacked Madrid. In the Basque country, the Republicans managed to form a respectable force of 30,000 men between Basque volunteers, Socialist, atheist, anarchist, Republicans and Communists. However, they suffered air support and motorized troops since the bulk of Soviet aid was destined for the capital.