From July 25 to November 16, 1938, the Battle of the Ebro was fought along the lower Ebro River in Catalonia, in the longest and largest battle of the Spanish Civil War. The Republican Army, under Colonel Juan Modesto, launched a surprise offensive across the river, initially achieving significant gains before being beaten back by the Nationalists' superior air power and artillery. The battle resulted in some 80,000 casualties and effectively destroyed the Republican Army as a fighting force, sealing the Republic's fate.

The Battle of the Ebro was the subject of some of the most powerful poetry of the war, with both sides chronicling the immense suffering and sacrifice. The battle's poetry often emphasized the river as a symbol of the divide between victory and defeat, and the Republican poets wrote of the heroic but futile crossing. The Ebro also inspired the poetry of the International Brigades, whose members fought in the battle and wrote of their final stand.