Escalating violence between left- and right-wing political factions boils over. Military officers stage a coup against a democratically elected, Soviet-backed, government. The country is thrown into chaos as centuries-old tensions return to the forefront. Hundreds of thousands of Spaniards choose sides and engage in the most devastating combat since the First World War. For loyalists to the Republic, the fight is seen as one for equality and their idea of progress. For the rebels, the struggle is a preemptive strike by tradition against an attempted communist takeover.

Thousands of foreigners, too, join the struggle. Most fight with the Soviet-sponsored International Brigades or other militias aligned with the loyalist "Republicans". Only a few side with the rebel "Nationalists". One of these rare volunteers for the Nationalists was Peter Kemp, a young British law student. Kemp, despite having little training or command of the Spanish language, was moved by the Nationalist struggle against international Communism. Using forged documents, he sneaked into Spain and joined a traditionalist militia, the Requetés, with which he saw intense fighting. Later, he volunteered to join the legendary and ruthless Spanish Foreign Legion, where he distinguished himself with heroism. Because of this bravery, he was one of the few foreign volunteers granted a private audience with Generalissimo Francisco Franco.

Kemp published his story... one of the only English accounts of the war from the Nationalist perspective, after a prestigious military career with the British Special Operations Executive during the Second World War.