Nazis test new air force, Luftwaffe, on Basque town of Guernica

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During the Spanish Civil War, the German military tests its powerful new air force—the Luftwaffe—on the Basque town of Guernica in northern Spain.

Although the independence-minded Basque region opposed General Francisco Franco’s Nationalist forces in the Spanish Civil War, Guernica itself was a small rural city of only 5,000 inhabitants that declared non-belligerence in the conflict. With Franco’s approval, the cutting-edge German aircraft began their unprovoked attack at 4:30 p.m., the busiest hour of the market day in Guernica. For three hours, the German planes poured down a continuous and unopposed rain of bombs and gunfire on the town and surrounding countryside. One-third of Guernica’s 5,000 inhabitants were killed or wounded, and fires engulfed the city and burned for days.