While he was making preparations to carry his design into execution, news came of the progress of Stephen of Serbia, which forced him to postpone it. Salonica, ‘one of the eyes of the empire,’ was in danger of surrendering to Stephen. The partisans of the Palaeologi among the population of that city were numerous. The neighbouring country was, however, under the power of the great Serbian, and unless Stephen were checked without delay the city would be given over to him. The old emperor sent word to his followers to remain steadfast, promising that he would come to their relief. In order to do so, he took a step which is sometimes incorrectly treated as the first important introduction of the Turks into Europe.[59] He induced his son-in-law, Orchan, to send a body of twenty thousand cavalry, under his son Suliman, across the Dardanelles to march against Stephen. The emperor left the capital as soon as he had heard that the Turks had crossed the straits to co-operate with them, and took his co-emperor John, who was obnoxious to the Turks, with him. For some reason which is not clear, the Othman or Ottoman Turks withdrew after they had crossed the Maritza, but the two emperors with another body of Turks went to Salonica and put an end to any design to surrender it. This was in 1349.
The history of the empire during the next six years is a medley of incidents, due to the hostility between the two emperors. John refused to address his elder colleague as emperor, and even proposed to join Stephen of Serbia, whose power in the Balkan peninsula was now greater than that of any other ruler. The Bulgarian king, appealed to by Cantacuzenus to enter into alliance against Stephen, refused his co-operation, and shortly after joined the Venetians to attack the empire.
Genoese and Venetians.
Cantacuzenus asked for the aid of the Genoese, who joined him in order to resist the Venetians. The rivalry during this reign between the two republics of Venice and Genoa was great. Each was at the height of its power, and the commerce and dominions of the empire were the principal objects of their rivalry. A hundred and fifty years earlier there had been colonies of Amalfians, Pisans, Anconans, Ragusans, and even Germans, within the walls of the city. All these had disappeared,[60] and Genoa the Superb and Venice, Queen of the Seas, were the sole Italian competitors for domination in or a share of the empire. At the period with which we are concerned they were about equally matched in strength, and the two brave republics were constantly fighting the battles of their great duel in the waters of the Greek empire. Within a few months the Genoese were alternately the allies and the enemies of Cantacuzenus. In 1350 a fleet of fourteen Venetian galleys, and another of Catalans, prevented the Genoese from entering the Bosporus. Two years later another formidable fleet of Venetian galleys joined one of twenty-six Spaniards in order to attack the Genoese. After Pisani, the Venetian admiral, had rested his men for two days on the island of Prinkipo, he joined the imperial ships at Heptaskalion, and with a fleet of sixty-eight vessels attacked the Genoese. The fleet of the latter, numbering seventy ships, was at Chalcedon, and tried to intercept the enemy when they endeavoured to make their way to the Golden Horn. In a battle which was fought at the mouth of the Bosporus while a strong south wind was blowing with a heavy sea—a battle which continued all night—both sides lost heavily. Eighteen Genoese ships were sunk. Pisani withdrew to Therapia, with a loss of sixteen ships. Galata, held by the Genoese, was not attacked, on account of the prevalence of Black Death,[61] or possibly because he heard that seventy or eighty other galleys were on their way to aid the Genoese.
Immediately afterwards the Genoese joined with the Turks, and transported across the Bosporus a body of them to attack Constantinople. Cantacuzenus, in consequence, was obliged to make peace with his rivals in Galata by allowing them to include a large portion of additional territory within new walls,[62] as well as to take possession of Selymbria and Heraclia in Thrace. The Genoese thereupon once more became his allies. Orchan was ready to assist him, and again promised to send twenty thousand Turks to resist the party of John.
Once more Cantacuzenus endeavoured to come to terms with his colleague. The latter had also endeavoured to gain the aid of Orchan, but failed. John’s reply to the overture of his father-in-law was again to refuse to recognise that he had any right to the title of emperor. The followers of the rival emperors, Cantacuzeni and Palaeologi, were more bitter in their opposition than the leaders themselves, and the former in 1353 proclaimed Matthew, the son of Cantacuzenus, co-emperor with his father.
It is clear from the statement of Cantacuzenus himself that, as John grew older, his own party became weaker. The hopes of the people and of the nobles for a peaceful reign had been disappointed. Instead of having peace, the country had been disturbed by civil war. Serbia and Bulgaria had both recovered strength. The Turks had encroached on the imperial territories.
The emperor’s greatest offence was rightly considered to have been the employment of Turkish auxiliaries, and the permission granted to the captors to sell the captured Christians as slaves, or the inability to prevent them from doing so.[63] The patriarch Philotheus remonstrated with him on this account, and Cantacuzenus declares that he received the admonition as the voice of God, and promised to conform to it.[64] Probably because he recognised that his own popularity was waning, he had allowed his eldest son, Matthew, to be associated with him in the government, but though the son displayed great activity, and gathered round him a strong party, both he and his father were condemned by the popular judgment.
The account given by Cantacuzenus is that he was asked by the nobles to nominate his successor, that he deferred giving his answer, but went to consult the patriarch, who retired to a monastery and after a week sent word that he would not return to the court nor to his church unless the emperor would swear never to proclaim his son Matthew. Thereupon Cantacuzenus called together the senate, who declared for Matthew. Cantacuzenus protests that in the struggle going on between John, his son-in-law, and Matthew he was always neutral, but that as the nobles wanted the latter he consented to name him as his colleague and successor. Thereupon Matthew was allowed to wear the purple buskin and the other imperial insignia. His name, as well as that of his father and Anne, the mother of John, was mentioned in the public prayers, while that of John was omitted.[65] The patriarch, however, remained obdurate. Matthew had not yet been consecrated. An assembly of bishops declared that, notwithstanding the patriarch’s opposition, he ought to be asked to perform the ceremony. The answer of Philotheus was to decree excommunication against any one who should attempt to lay upon him such a duty. The patriarch was threatened with dismissal. He replied that he would be glad of it, and was dismissed accordingly.[66]