26MAY-1421 :- Death Of Mehmed I, Ottoman sultan.

Mehmed I Çelebi 
(1381– May 26, 1421) was the sultan of the Ottoman Empire (Rûm) from 1413 to 1421. He was one of the sons of Bayezid I and Devlet Hatun.

Born in Bursa in 1390 to sultan Bayezid I and one of his wives, Devlet Hatun, Mehmed was the third oldest son of Bayezid. Along with his brothers from various mothers, including Süleyman Çelebi, İsa Çelebi, Mustafa Çelebi, and Musa Çelebi, Mehmed had the title Çelebi, meaning "gentleman."

On July 20, 1402, Bayezid was defeated in the Battle of Ankara by the Turko-Mongol conqueror and ruler Tamerlane. The brothers (with the exception of Mustafa, who was captured and taken along with Beyazid to Samarkand) were rescued from the battlefield, Mehmed being saved by Bayezid Pasha, who took him to his hometown of Amasya. Mehmed later made Bayezid Pasha his grand vizier (1413–1421).

After the battle, Mehmed fought with his brothers Süleyman, İsa, and Musa in the civil war known as the Ottoman Interregnum from 1402 to 1413, emerging victorious with the other three brothers dead. His other brother Mustafa would later emerge from hiding during Mehmed's reign and fight two failed rebellions against him and his son, Murat II.