Tiberius succeeded Augustus as Roman emperor in 14 AD after the death of Augustus. Tiberius continued the centralization of power to the emperor. It became really only one man in charge of Rome when Tiberius went into seclusion after his sons death and the government came to a halt. The mentally unstable Gaius more commonly known as Caligula succeeded Tiberius as emperor. He ruled for four years, in which he ordered the heads of statues to be cut off so that he could put his own head on them. After a brutal four years the praetorian guard assassinated him. The more competent emperor Claudius succeeded him for a more peaceful 13 year reign. After him Nero became emperor for 14 years. The story goes that for the first five years of his reign he was more stable but after that he became vicious and brutal. In an invasion from Gaul he committed suicide believing that they were hopelessly outnumbered. This marked the end of the Julio – Claudian dynasty.
The year that followed became known as the year of the four emperors as emperors were announced and ousted in rapid succession. Then Vespasian stabilized Rome and he became emperor for 10 years. His son Titus succeeded him and ruled competently for two years. After the death of Titus Vespasians other son Domitian became emperor. He ruled for 15 years and started out fine but after a revolt lead by the governor of a Roman province he became suspicious of everyone. He demanded worship of him and his family and had extra priests for worship of himself. Finally his family assassinated him which brought an end to the Flavian dynasty. During this time there was no legitimate way of naming the emperor sometimes the praetorian guard decided, sometimes it passed from father to son, and sometimes legions appointed their generals as emperor. Because of this system brutal or incompetent people could be appointed which was often the case.