It is modern art's most powerful antiwar statement... created by the twentieth century's most well-known and least understood artist. But the mural called Guernica is not at all what Pablo Picasso has in mind when he agrees to paint the centerpiece for the Spanish Pavilion of the 1937 World's Fair.

For three months, Picasso has been searching for inspiration for the mural, but the artist is in a sullen mood, frustrated by a decade of turmoil in his personal life and dissatisfaction with his work. The politics of his native homeland are also troubling him, as a brutal civil war ravages Spain. Republican forces, loyal to the newly elected government, are under attack from a fascist coup led by Generalissimo Francisco Franco. Franco promises prosperity and stability to the people of Spain. Yet he delivers only death and destruction.

Hoping for a bold visual protest to Franco's treachery from Spain's most eminent artist, colleagues and representatives of the democratic government have come to Picasso's home in Paris to ask him to paint the mural. Though his sympathies clearly lie with the new Republic, Picasso generally avoids politics - and disdains overtly political art.

The official theme of the Paris Exposition is a celebration of modern technology. Organizers hope this vision of a bright future will jolt the nations out of the economic depression and social unrest of the thirties.

As plans unfold, much excitement is generated by the Aeronautics Pavilion, featuring the latest advances in aircraft design and engineering. Who would suspect that this dramatic progress would bring about such dire consequences?

On April 27th, 1937, unprecedented atrocities are perpetrated on behalf of Franco against the civilian population of a little Basque village in northern Spain. Chosen for bombing practice by Hitler's burgeoning war machine, the hamlet is pounded with high-explosive and incendiary bombs for over three hours. Townspeople are cut down as they run from the crumbling buildings. Guernica burns for three days. Sixteen hundred civilians are killed or wounded.

By May 1st, news of the massacre at Guernica reaches Paris, where more than a million protesters flood the streets to voice their outrage in the largest May Day demonstration the city has ever seen. Eyewitness reports fill the front pages of Paris papers. Picasso is stunned by the stark black and white photographs. Appalled and enraged, Picasso rushes through the crowded streets to his studio, where he quickly sketches the first images for the mural he will call Guernica. His search for inspiration is over.

From the beginning, Picasso chooses not to represent the horror of Guernica in realist or romantic terms. Key figures - a woman with outstretched arms, a bull, an agonized horse - are refined in sketch after sketch, then transferred to the capacious canvas, which he also reworks several times. "A painting is not thought out and settled in advance," said Picasso. "While it is being done, it changes as one's thoughts change. And when it's finished, it goes on changing, according to the state of mind of whoever is looking at it."

Three months later, Guernica is delivered to the Spanish Pavilion, where the Paris Exposition is already in progress. Located out of the way, and grouped with the pavilions of smaller countries some distance from the Eiffel Tower, the Spanish Pavilion stood in the shadow of Albert Speer's monolith to Nazi Germany. The Spanish Pavilion's main attraction, Picasso's Guernica, is a sober reminder of the tragic events in Spain.

Initial reaction to the painting is overwhelmingly critical. The German fair guide calls Guernica "a hodgepodge of body parts that any four-year-old could have painted." It dismisses the mural as the dream of a madman. Even the Soviets, who had sided with the Spanish government against Franco, react coolly. They favor more overt imagery, believing that only more realistic art can have political or social consequence. Yet Picasso's tour de force would become one of this century's most unsettling indictments of war.

After the Fair, Guernica tours Europe and Northern America to raise consciousness about the threat of fascism. From the beginning of World War II until 1981, Guernica is housed in its temporary home at the Museum of Modern Art in New York, though it makes frequent trips abroad to such places as Munich, Cologne, Stockholm, and even Sao Palo in Brazil. The one place it does not go is Spain. Although Picasso had always intended for the mural to be owned by the Spanish people, he refuses to allow it to travel to Spain until the country enjoys "public liberties and democratic institutions."

Speculations as to the exact meaning of the jumble of tortured images are as numerous and varied as the people who have viewed the painting. There is no doubt that Guernica challenges our notions of warfare as heroic and exposes it as a brutal act of self-destruction. But it is a hallmark of Picasso's art that any symbol can hold many, often contradictory meanings, and the precise significance of the imagery in Guernica remains ambiguous. When asked to explain his symbolism, Picasso remarked, "It isn't up to the painter to define the symbols. Otherwise it would be better if he wrote them out in so many words! The public who look at the picture must interpret the symbols as they understand them."

In 1973, Pablo Picasso, the most influential artist of the twentieth century, dies at the age of ninety-two. And when Franco dies in 1975, Spain moves closer to its dream of democracy. On the centenary of Picasso's birth, October 25th, 1981, Spain's new Republic carries out the best commemoration possible: the return of Guernica to Picasso's native soil in a testimony of national reconciliation. In its final journey, Picasso's apocalyptic vision has served as a banner for a nation on its path toward freedom and democracy.

Now showcased at the Reina Sofía, Spain's national museum of modern art, Guernica is acclaimed as an artistic masterpiece, taking its rightful place among the great Spanish treasures of El Greco, Goya and Velazquez. "A lot of people recognize the painting," says art historian Patricia Failing. "They may not even know that it's a Picasso, but they recognize the image. It's a kind of icon."