“The racial pride of this mysterious people has always revolved around the sacred oak of Guernica, beneath whose branches the laws of the Basques were promulgated and the Kings of Spain swore to respect their privileges” – Jan Morris
Guernica was bombed at the invitation of General Franco and the Nationalists during the Spanish Civil War because the Basque Country was a stronghold of the Republicans and because it was a symbol of Basque nationalism. It was of no real strategic military importance but Franco wanted to end the war in the north as quickly as possible and to do so he needed to take Bilbao and this act of aggression demonstrated his power.
Have Bag, Will Travel 