The New Dictionary of Cultural Literacy, Third Edition. 2002.
Nero
(NEER-oh) An ancient Roman emperor, famed for his cruelty. He had his mother and wife killed and kicked his mistress to death while she was pregnant. Nero also persecuted Christians, blaming them for a great fire in Rome. According to tradition, he put the ApostlesPeter and Paul to death.
A famous legend holds that Nero caused the great fire of Rome himself and played a violin while watching it. To say that someone is fiddling while Rome burns is to say that the person is indifferent to catastrophe.