After the defeat of the Serbs and Bosniaks in the Battle of Kosovo on 15 June 1389, Ivan Shishman had to seek help from Hungary. During the winter of 1391–1392, he entered into secret negotiations with the King of Hungary Sigismund, who was planning a campaign against the Turks. The new Ottoman sultan Bayezid I pretended to have peaceful intentions in order to cut off Ivan Shishman from his alliance with the Hungarians.

However, in the spring of 1393 Bayezid gathered a large army from his dominions in the Balkans and Asia Minor and attacked Bulgaria. The Ottomans marched to the capital Tarnovo and besieged it. He entrusted the main command to his son Celebi, and ordered him to depart for Tarnovo. Suddenly, the town was besieged from all sides. The Turks threatened the citizens with fire and death if they did not surrender.

The population resisted but eventually surrendered after a three-month siege, following an attack from the direction of Tsarevets, on July 17, 1393. The Patriarch's church "Ascension of Christ" was turned into a mosque, the rest of the churches were also turned into mosques, baths, or stables. All palaces and churches of Trapezitsa were burned down and destroyed. The same fate was expected for the tzar palaces of Tsarevets; however, parts of their walls and towers were left standing until the 17th century.