text: While Vespasian was preparing to besiege the city of Jerusalem during the latter campaign , emperor Nero committed suicide , plunging the empire into a year of civil war known as the Year of the Four Emperors .
simplified: While Vespasian was preparing to besiege Jerusalem during the latter campaign , emperor Nero committed suicide , plunging the empire into a year of civil war known as the Year of the Four Emperors .