http://www.msdlists.com/Picasso Guernica.html
Pablo Picasso (1881- 1973) was working on Guernica at the time of the Nazi German bombing of Guernica, Spain, by twenty-four bombers, on April 26, 1937 during the Spanish Civil War. He then named the painting after the town. In that air raid an estimated 250 to 1,600 were killed and large number of others were injured.
The mural was produced under a commission by the Spanish Republican government to decorate the Spanish Pavilion at the Paris International Exposition (the 1937 World's Fair in Paris). Picasso said as he worked on the mural:
“The Spanish struggle is the fight of reaction against the people, against freedom. My whole life as an artist has been nothing more than a continuous struggle against reaction and the death of art. How could anybody think for a moment that I could be in agreement with reaction and death? ... In the panel on which I am working, which I shall call Guernica, and in all my recent works of art, I clearly express my abhorrence of the military caste which has sunk Spain in an ocean of pain and death."
http://en.wikipedia.org/wiki/Guernica_(painting)
Guernica is a painting by Pablo Picasso, depicting the bombing of Guernica, Spain, by German and Italian warplanes at the behest of the Spanish Nationalist forces, on April 26, 1937, during the Spanish Civil War. The Spanish Republican government commissioned Pablo Picasso to create a large mural for the Spanish display at the Exposition Internationale des Arts et Techniques dans la Vie Moderne (1937) Paris International Exposition in the 1937 World's Fair in Paris.
Guernica shows the tragedies of war and the suffering it inflicts upon individuals, particularly innocent civilians. This work has gained a monumental status, becoming a perpetual reminder of the tragedies of war, an anti-war symbol, and an embodiment of peace. On completion Guernica was displayed around the world in a brief tour, becoming famous and widely acclaimed. This tour helped bring the Spanish Civil War to the world's attention.
Analysis of the symbolism http://en.wikipedia.org/wiki/Guernica_(painting)#Symbolism_and_interpretations
Also;
http://www.spanish-fiestas.com/art/picasso-guernica.htm
http://www.danstopicals.com/guernica.htm
PS.
(Sadly).
It's in the Museo Reina Sofia, Madrid
349 cm × 776 cm (137.4 in × 305.5 in)