On August 14, 1936, Nationalist forces under General Juan Yagüe stormed and captured the fortified border city of Badajoz, Extremadura, after several days of shelling and street fighting. The battle cut off the Spanish Republic from neighboring Portugal and linked the northern and southern zones of Nationalist control. Following the battle, Nationalist troops carried out a massacre of Republican supporters, with estimates of the dead ranging from 500 to 4,000, in one of the worst atrocities of the war.

The Battle of Badajoz and its aftermath were memorialized in numerous poems, with left-wing writers denouncing the massacre as a crime against humanity. The event became a symbol of Nationalist brutality in Republican poetry, while right-wing poets celebrated the victory as a necessary step in the crusade against communism. The massacre also inspired international poets, including Pablo Neruda, who wrote of the 'blood of Badajoz' in his verses.