George Steer, a British journalist covering the Spanish Civil War wrote a now infamous description of the bombing of Guernica, bringing the atrocity to the world's attention and exposing German involvement.
His words inspired Pablo Picasso to paint what, for many, is his masterpiece, which depicts the casualties of the bombing, carried out by the German Luftwaffe.
"In the form of its execution and the scale of the destruction it wrought, no less than in the selection of its objective, the raid on Guernica is unparalleled in military history," Steer wrote.
And it was indeed unparalleled: the first time a civilian population was subjected to a large-scale bombing campaign by a modern air force, it would become the precursor to the horrors that awaited Europe during the Second World War.
Steer's article appeared in both The Times and The New York Times and his story has now been made into an English-language film, the first depicting the horrific bombing that came to symbolize the destruction of the Spanish Civil War.
The premiere of Gernika - which uses the Basque spelling of the town - will take place at the Malaga Film Festival on Tuesday, 26th April, the 79th anniversary of the bombing.
Guernica after the bombing. Photo: AFP
"When they offered me the film the first thing I thought was 'again!' but afterwards I realized that, on the contrary, film has never dealt with this subject," director Koldo Serra, himself from the Basque Country, told Spanish daily El Mundo.
"I don't know why there is this silence, maybe it is still a taboo subject but it touches me very closely. I have many friends whose grandparents were there and I have grown up with the story of Guernica," added the director, who was born in Bilbao.
In the film, a joint Spanish-US production, George Steer becomes Henry, an American, played by British actor James D'Arcy. He crosses paths with Teresa, played by Spanish actress Maria Valverde, a censor for the Republicans in Guernica.
Serra has taken real accounts from people who lived through the bombings to construct an accurate backdrop to the central characters' love story.
The Spanish-language trailer for Gernika.
German aircraft bombed the town of Guernica, a base for many republican fighters, on behalf of the nationalists, led by General Francisco Franco who would go on to become dictator of Spain until his death in 1975.
Basque estimates put the dead at up to 1,500, but the number is still disputed to this day. Steer wrote how "Guernica was not a military objective"; two army barracks and a factory making war materials located outside the town were untouched.
"The object of the bombardment was seemingly the demoralization of the civil population and the destruction of the cradle of the Basque race," he wrote.
George Steer was commemorated with a statue in the town in 2006 and has a road named after him in Bilbao.