It was the papacy, under Pope Gregory I (”the Great”; 590-604) in 590, that rescued Rome from its demise. In an eerie reflexion of the empire, Gregory sent missions all over Europe to spread the word of the Church and publicize its holy relics, so drawing pilgrims, and their money, back to the city, and in time making the papacy the natural dominance in Rome. The pope took the study “Pontifex Maximus” after the title of the high priest of classical times (literally “the keeper of the bridges”, which were vital to the city’s well-being). Four of the city’s great basilicas were built during this time, along with a great many other primeval Christian churches, underlining the city’s phoenix-like resurrection under the popes, who as well as building their own new structures converted those Roman buildings that were still standing - for example fortifying the Castel Sant’Angelo to repel invaders. The crowning a couple of centuries later of Charlemagne as Holy Roman Emperor, with dominions spread Europe-wide but answerable to the pope, intensified the city’s revival, and the pope and city became recognized as head of the Christian world. There were times over the next few hundred years when the power of Rome and the papacy was weakened: Robert Guiscard, the Norman king, sacked the city in 1084; a century later, a dispute between the city and the papacy led to a series of popes relocating in Viterbo; and in 1308 the French-born Pope Clemente V (1305-16) transferred his court to Avignon. In the mid-fourteenth century, Cola di Rienzo seized power, setting himself up as the people’s saviour from the decadent ways of the city’s rulers and forming a new Roman republic. But the increasingly autocratic ways of the new ruler soon lost popularity; Cola di Rienzo was deposed, and in 1376 Pope Gregory XI (1370-78) returned to Rome.