His operative fingers were the index and middle; as the result of a 1928 fire (aged 18), his ring and pinky fingers were useful ever-after only for bar chords. Those flashy, arpeggiated runs you hear are the work of just two fingers.
He was a gypsy. He was a gypsy in Western Europe when Hitler came to power.
per Wikipedia: 'Reinhardt survived the war unscathed, unlike the many Romanis who perished in the Porajmos, the Nazi regime's systematic murder of several hundred thousand European Romanis. He was especially fortunate because the Nazi regime did not allow jazz to be performed and recorded. He apparently enjoyed the protection of Luftwaffe officer Dietrich Schulz-Kohn, nicknamed "Doktor Jazz", who deeply admired his music.'
It was a brain hemorrhage that killed him in 1953.