The crossword solution for the term 'QUO VADIS? EMPEROR' is NERO, which refers to the Roman Emperor Nero Claudius Caesar Augustus Germanicus. Nero was the last emperor of the Julio-Claudian dynasty and ruled from 54 to 68 AD. He is known for his extravagance and cruelty, as well as his persecution of Christians. The phrase 'Quo Vadis?' is attributed to him, as it is said that he asked this question when he encountered Saint Peter on the road to Rome.