The Ottoman Threat 1396-1502
HIS personal status as a ghazi leader enhanced by his great victory at Nicopolis, Sultan Bayezid I was able immediately to resume his twin strategies of unifying Anatolia and tightening the noose on Constantinople (see map 4). In 1397 the Sultan occupied Konya and destroyed the state of Karaman, after defeating Alauddin Ali Bey at the plain of Akcay. In the following year the death of Qadi Burhan al-Din enabled Bayezid to establish his suzerainty over the former's large territories in central Anatolia. The Ottomans were now in direct contact with the Mamluk lands, and in 1398-9 the Sultan penetrated the Euphrates Valley, taking Malatya and Elbistan. By 1400 most of Cilicia was in Ottoman hands, and Anatolia was virtually united. At the same time the siege of Constantinople, begun in 1394, was renewed. Its most important feature was the construction of a fortress, Anadolu Hisar, on the Asian side of the Bosphorus, in order to control Byzantine access to the Black Sea. Famine conditions prevailed in the city in 1397.
With hindsight it is clear that Bayezid could only have taken Constantinople if he had concentrated all his resources on the task, but the danger appeared grave enough to the Emperor Manuel II, and in 1397-8 he sent urgent appeals to the West. It is interesting that even in the wake of Nicopolis these met with some response, for in 1398, 1399, and 1400 the Roman Pope Boniface IX ordered crusade preaching to raise funds for the Emperor, and in 1399 Charles VI of France sent Marshal Boucicaut with a 'task force' of about 1,200 men to aid in the defence. Most of these troops returned with Boucicaut in December after a few months' desultory campaigning in the vicinity of Constantinople. But a small garrison remained in the city, and Manuel was encouraged to undertake a personal