|Period||Rise of the Ottoman Empire|
|Royal House||House of Osman|
|Valide Sultan||Gülçiçek Hatun|
Bayezid I (Ottoman: بايزيد اول, Turkish: Beyazıt, nicknamed Yıldırım (Ottoman: ییلدیرم), "the Thunderbolt"; 1354 – March 8, 1403) was the Sultan of the Ottoman Empire, from 1389 to 1402. He was the son of Murad I and Valide Sultan Gülçiçek Hatun.
Bayezid ascended to the throne following the death of his father Murad I, who was killed by Serbian knight Miloš Obilić during (June 15), or immediately after (June 16), the Battle of Kosovo in 1389, by which Serbia became a vassal of the Ottoman Empire. Immediately after obtaining the throne, he had his younger brother strangled to avoid a plot. In 1390, Bayezid took as a wife Princess Olivera Despina, the daughter of Prince Lazar of Serbia, who also lost his life in Kosovo. Bayezid recognized Stefan Lazarević, the son of Lazar, as the new Serbian leader (later despot), with considerable autonomy.
From 1389 to 1395 he conquered Bulgaria and northern Greece. In 1394 he crossed the River Danube to attack Wallachia, ruled at that time by Mircea the Elder. The Ottomans were superior in number, but on October 10, 1394 (or 17 May 1395), in the Battle of Rovine, on forested and swampy terrain, the Wallachians won the fierce battle and prevented Bayezid from conquering the country.
In 1394, Bayezid laid siege to Constantinople, the capital of the Byzantine Empire. Anadoluhisarı fortress was built between 1393 and 1394 as part of preparations for the Second Ottoman Siege of Constantinople, which took place in 1395. On the urgings of the Byzantine emperor Manuel II Palaeologus a new crusade was organized to defeat him. This proved unsuccessful: in 1396 the Christian allies, under the leadership of the King of Hungary and future Holy Roman Emperor (in 1433) Sigismund, were defeated in the Battle of Nicopolis. Bayezid built the magnificent Ulu Camii in Bursa, to celebrate this victory.
In 1400, the Central Asian warlord Timur had succeeded in rousing the local Turkic beyliks that had been vassals of the Ottomans to join him in his attack on Bayezid, who was considered one of the most powerful rulers in the Muslim world during that period. In the fateful Battle of Ankara, on 20 July 1402, Bayezid was captured by Timur and the Ottoman army was overpowered. Bayezid's sons, however, escaped from the battlefield, and later they would start civil war (see also Ottoman Interregnum). Many writers claim that Bayezid was mistreated by the Timurids. However, writers and historians from Timur's own court reported that Bayezid was treated well, and that Timur even mourned his death.
In fiction 
The defeat of Bayezid became a popular subject for later western writers, composers and painters. They revelled in the legend that he was taken by Timur to Samarkand, and embellished it with a cast of characters to create an oriental fantasy that has maintained its appeal. Christopher Marlowe's play Tamburlane the Great was first performed in London in 1587, three years after the formal opening of English-Ottoman trade relations when William Harborne sailed for Constantinople as agent of the Levant Company. In 1648 there appeared the play Le Gran Tamerlan et Bejezet by Jean Magnon, and in 1725 Handel's Tamerlano was first performed and published in London; Vivaldi's version of the story, Bajazet, was written in 1735. Magnon had given Bayezid an intriguing wife and daughter; the Handel and Vivaldi renditions included, as well as Tamerlane and Bayezid and his daughter, a prince of Byzantium and a princess of Trebizond (Trabzon) in a passionate and incredible love story. A cycle of paintings in Schloss Eggenberg, near Graz in Austria, translated the theme to a different medium; this was completed in the 1670s shortly before the Ottoman army attacked the Habsburgs in central Europe. Bayezid (spelt Bayazid) is a central character in the Robert E. Howard story Lord of Samarcand.
A Commando Battalion in the Pakistan Army is named Yaldaram Battalion after him.
Marriages and progeny 
- (m. 1381) - Devlet Shah Hâtûn - Daughter of Süleyman Shah (Şah Çelebi) of Germiyanids;
- Devlet Hâtûn - Daughter of Yakub Shah of Germiyanids, Descendant of Rumi through his son Sultan Walad's daughter Mutahhara Hatun who was an ancestor of Yakub Shah;
- Hafsa Hatun - Daughter of Isa Bey of Aydinids;
- Sultan Hatun - Daughter of Süleyman Shah of Dulkadirids;
- Olivera Lazarević - Despina Hâtûn - Daughter of Prince Lazar of Serbia;
- Maria, Princess of Hungary, daughter of János, Count of Hungary, whose second husband was Payo Gómez de Sotomayor;
- Angelina Hatun
- Süleyman Çelebi (1377-1411), Co- Sultan of Rumelia
- İsa Çelebi (1380-1406), Governor of Anatolia ( Balıkesir and Bursa ) - son of Devlet Hatun
- Mehmed Çelebi (1389-1421), Governor of Anatolia ( Amasya ) and later as Ottoman Sultan Mehmed I Çelebi, (1413–1421) - son of Devlet Hatun
- Mustafa Çelebi (1393-1422), son of Devlet Shah Hatun
- Musa Çelebi (d. 1413), Sultan of Rumelia (1410–1413) - son of Devlet Shah Hatun
- Musa - son of Angelina
- Kasım - son
- Yusuf - son, converted to Christianity, changed his name to Demetrios
- Erhondu - daughter
- Hundi - daughter
- Fatma - daughter
- Lowry, Heath W. (2003) The Nature of the Early Ottoman State. Albany, NY: State University of New York Press, p. 153
- Runciman, Steven The Fall of Constantinople. Cambridge: Cambridge University Press, p. 36
- Bayezid I, Halil Inalcik,The Encyclopedia of Islam, Vol. I, Ed. H.A.R.Gibb, J.H.Kramers, E. Levi-Provencal and J.Schacht, (Brill, 1986), 1118.
- Mango, Cyril. The Oxford History of Byzantium. 1st ed. New York: Oxford UP, 2002. p. 273-4
- Nancy Bisaha, Creating East And West: Renaissance Humanists And the Ottoman Turks, (University of Pennsylvania Press, 2004), 98.
- Dimitris J. Kastritsis, The Sons of Bayezid: Empire Building and Representation in the Ottoman Civil War of 1402-13, (Brill, 2007), 5.
- Dimitris J. Kastritsis,1-3.
- London: Printed & sold by J. Cluer, 
- Finkel, C. (2006) The History of the Ottoman Empire: Osman's Dream. New York: Basic Books; p. 30
- Howard, Robert E. (1973) Sowers of the Thunder, Ace Science Fiction
- Shaw, Stanford Jay (1976) History of the Ottoman Empire and Modern Turkey; Vol. 1: Empire of the Gazis; the rise and decline of the Ottoman Empire, 1280-1808. Cambridge: Cambridge University Press ISBN 0-521-21280-4; p. 28
- Dimitris J. Kastritsis, 41.
- Goodwin, Jason (1998) Lords of the Horizons. London: Chatto & Windus
- Harris, Jonathan (2010) The End of Byzantium. New Haven and London: Yale University Press ISBN 978-0-300-11786-8
- Imber, Colin (2002) The Ottoman Empire. London: Palgrave/Macmillan ISBN 0-333-61387-2
- Nicolle, David (1999) Nicopolis 1396: The Last Crusade. Oxford: Osprey Books ISBN 978-1-85532-918-8
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Bayezid IBorn: 1354 Died: March 8, 1403[aged 47–48]
|Sultan of the Ottoman Empire
1389 – March 8, 1403