The civil war that tore Spain apart between 1936 and 1939 and attracted liberals and socialists from across the world to support the cause against Franco was one of the most hard-fought and bitterest conflicts of the 20th century: a war of atrocities and political genocide and a military testing ground before WWII for the Russians, Italians and Germans, whose Condor Legion so notoriously destroyed Guernica. This was Antony Beevor's first work of non-fiction, pre-dating his international...