On 26 April 1937, Nazi German and Italian bombers attacked the Basque city of Guernica. Over the course of three hours, they destroyed three-quarters of the ancient town, killing and wounding hundreds. The raid was “unparalleled in military history”, according to reports at the time – and it inspired one of the most famous anti-war paintings in history. A new exhibition staged in London by Barcelona’s Mayoral Gallery honours a group of artists who responded to the atrocities of the Spanish Civil War.

These artists were brought together by the 1937 Paris Exhibition, which opened less than a month after the bombing and just 10 months after the Civil War began. The Exhibition is usually remembered for the competing bluster of two nations: Germany, with its monumental granite tower topped with a giant eagle and swastika, and the Soviet Union, whose marble-clad structure was capped by an even bigger statue of two figures clutching a hammer and a sickle. Yet it also played host to a humbler project that has outlasted either monolith. Mayoral’s exhibition commemorates the 80th anniversary of the Spanish pavilion, seen by the Second Spanish Republic as a way of revealing General Franco’s cruelty to the rest of the world against a backdrop of rising authoritarianism.

Its ambitions were far removed from Nazi and Soviet architectural one-upmanship. As Europe moved towards war, the situation in Spain took on significance around the world. It became a battleground for the forces of Fascism and Communism and inspired new works from some of the greatest artists of the time. Pablo Picasso, Julio González, Joan Miró, Alexander Calder, Alberto Sánchez, and José Gutiérrez Solan were all shown in the Spanish pavilion.