1937 : Nazis test Luftwaffe on Guernica

During the Spanish Civil War, the German military tested 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 nonbelligerence 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.

The indiscriminate killing of civilians at Guernica aroused world opinion and became a symbol of fascist brutality. Unfortunately, by 1942, all major participants in World War II had adopted the bombing innovations developed by the Nazis at Guernica, and by the war's end, in 1945, millions of innocent civilians had perished under Allied and Axis air raids.
Guernica is a painting by Pablo Picasso, which he was already working on at the time of the Nazi German bombing of Guernica, Spain, by twenty-four bombers, on April 26, 1937 during the Spanish Civil War, and which he decided to name after it. In any case, a number of people variously estimated between 250 and 1,600 were killed in the air raid and many more were injured.