When and how did Bulgaria and Serbia come under the rule of the Ottoman Turks?

The Turks appeared in the Balkans in 1351, when they intervened in the conflict within Byzantium and were able to capture the Cimpe fortress. The process of conquering Bulgaria was mainly completed by Sultan Bayazid I by 1396, it was in that year that he defeated the army of European knights near Nikopol.

By 1422, the Turks captured the remains of the territory of the Vidin kingdom, where the Asenei dynasty ruled, and in 1430 they created the Ottoman sanjak (administrative unit) on its territory.

The conquests of Serbia began in the 1380s, one of the episodes was the battle on the Kosovo field in 1389, in 1439 the Turks captured the Smederovo fortress near Belgrade, and by 1459 they had conquered Serbia as a whole, although Belgrade was taken only in 1521-1522, it was controlled by the Hungarian king.

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