Cola di Rienzo and the Pope's return to Rome.  
In spite of its decline and the absence of the Pope, Rome had not lost its spiritual prestige: in 1341 the famous poet Petrarca came to the city to be crowned as Poet laureate in Capitoline Hill. Noblemen and poor people at one time demanded with one voice the return of the Pope. Among the many ambassadors that in this period took their way to Avignon, emerged the bizarre but eloquent figure of Cola di Rienzo. As his personal power among the people increased by time, on 20 May 1347 he conquered the Capitoline at the head of an enthusiastic crowd. The period of his power, though very short-lived, aspired to the prestige of Ancient Rome. Now in possession of dictatorial powers, he took the title of "tribune", referring to the pleb's magistracy of the Roman Republic. Cola also considered himself at an equal status of that of the Holy Roman Emperor. On 1 August, he conferred Roman citizenship on all the Italian cities, and even prepared for the election of a Roman emperor of Italy. It was too much: the Pope denounced him as heretic, criminal and pagan, the populace had begun to be disenchanted with him, while the nobles had always hated him. On 15 December, he was forced to flee.   
In August 1354, Cola was again a protagonist, when Cardinal Gil Alvarez De Albornoz entrusted him with the role of "senator of Rome" in his programme of reassuring the Pope's rule in the Papal States. In October the tyrannical Cola, who had become again very unpopular for his delirious behaviour and heavy bills, was killed in a riot provoked by the powerful family of the Colonna. In April 1355, Charles IV of Bohemia entered the city for the ritual coronation as Emperor. His visit was very disappointing for the citizens. He had little money, received the crown not from the Pope but from a Cardinal, and moved away after a few days.  
With the emperor back in his lands, Albornoz could regain a certain control over the city, while remaining in his safe citadel in Montefiascone, in the Northern Lazio. The senators were chosen directly by the Pope from several cities of Italy, but the city was in fact independent. The Senate council included six judges, five notaries, six marshals, several familiars, twenty knights and twenty armed men. Albornoz had heavily suppressed the traditional aristocratic families, and the "democratic" party felt confident enough to start an aggressive policy. In 1362 Rome declared war on Velletri. This move, however, provoked a civil war. The countryside party hired a condottieri band called "Del Cappello" ("Hat"), while the Romans bought the services of German and Hungarian troops, plus a citizen levy of 600 knights and even 22,000 infantry. This was the period in which condottieri bands were active in Italy. Many of the Savelli, Orsini and Annibaldi expelled from Rome became leaders of such military units. The war with Velletri languished, and Rome again gave itself to the new Pope, Urban V, provided Albornoz did not enter the walls.  
On 16 October 1367, in reply to the prayers of St Brigid and Petrarca, Urban finally visited for the city. During his presence, Charles IV was again crowned in the city (October 1368). In addition, the Byzantine emperor John V Palaeologus came in Rome to beg for a crusade against the Ottoman Empire, but in vain. However, Urban did not like the unhealthy air of the city, and on 5 September 1370 he sailed again to Avignon. His successor, Gregory XI, officially set the date of his return to Rome at May 1372, but again the French cardinals and the King stopped him.  
Only on 17 January 1377, Gregory XI could finally reinstate the Holy See in Rome.  
Western schism and conflict with Milan.  
The incoherent behaviour of his successor, the Italian Urban VI, provoked in 1378 the Western Schism, which impeded any true attempt of improving the conditions of the decaying Rome. The 14th century, with the absence of the popes during the Avignon Papacy, had been a century of neglect and misery for the city of Rome, which dropped to its lowest level of population. With the return of the papacy to Rome repeatedly postponed because of the bad conditions of the city and the lack of control and security, it was first necessary to strengthen the political and doctrinal aspects of the pontiff.  
When in 1377 Gregory XI was in fact returned to Rome, he found a city in anarchy because of the struggles between the nobility and the popular faction, and in which his power was now more formal than real. There followed four decades of instability, characterised by the local power struggle between the commune and the papacy, and internationally by the great Western Schism, at the end of which was elected Pope, Martin V. He restored order, laying the foundations of its rebirth.  
In 1433 the Duke of Milan, Filippo Maria Visconti signed a peace treaty with Florence and Venice. He then sent the condottieri Niccolò Fortebraccio and Francesco Sforza to harass the Papal States, in vengeance for Eugene IV's support to the two former republics.  
Fortebraccio, supported by the Colonna, occupied Tivoli in October 1433 and ravaged Rome's countryside. Despite the concessions made by Eugene to the Visconti, the Milanese soldiers did not stop their destruction. This led the Romans, on 29 May 1434 to institute a Republican government under the Banderesi. Eugene left the city a few days later, during the night of 4 June.  
However, the Banderesi proved incapable of governing the city, and their inadequacies and violence soon deprived them of popular support. The city was therefore returned to Eugene by the army of Giovanni Vitelleschi on 26 October 1434. After the death in mysterious circumstances of Vitelleschi, the city came under the control of Ludovico Scarampo, Patriarch of Aquileia. Eugene returned to Rome on 28 September 1443. 

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