Already years before the Nazis came to power, German scientists were propagating theories about blood purity. Though this obsession led to bizarre and dangerous theories about superiority and personality traits, it also led to medical breakthroughs.
For the majority of humanity, the outbreak of World War I was a catastrophe on an unprecedented scale. But for Ludwik Hirszfeld, it turned out to be a stroke of good fortune.
Together with his wife, Hanna, the German doctor ran a bacteriology lab in Thessaloniki, Greece, where he had nearly unlimited access to human test subjects -- the French, British, Italian, Russian and Serbian soldiers who made up the multinational Army of the Orient, stationed in this port city in northern Greece and hemmed in by German troops during the so-called Balkans Campaign of the war.
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