In September 1937, the Battle of El Mazuco was fought in Asturias as the last major Republican stand in the northern campaign. The battle, which took place in the rugged mountains of the Picos de Europa, saw Republican forces mount a desperate defense against the Nationalist advance. Although the Republicans fought bravely, they were ultimately overwhelmed, and the fall of Gijón on October 21 ended the War in the North, leaving the Republic isolated in the east and south.

The Battle of El Mazuco inspired a number of poems by Republican soldiers, who wrote of the heroic resistance in the mountains. The battle's poetry often evoked the landscape of Asturias, blending natural imagery with the tragedy of defeat. The fall of the north also inspired a sense of fatalism in Republican poetry, as writers began to confront the possibility of losing the war.