Bayezid I, also known as Bayezid the Thunderbolt, was the Ottoman Sultan from 1389 to 1402. He was the son of Murad I and played a significant role in expanding the Ottoman Empire. His reign is marked by military conquests, including the capture of Sofia and Thessaloniki, which strengthened Ottoman control in the Balkans. Bayezid I is also known for his conflict with Timur, a powerful Central Asian conqueror. This rivalry culminated in the Battle of Ankara in 1402, where Bayezid was defeated and captured. His defeat led to a temporary decline of the Ottoman Empire, known as the Interregnum.