View source for Murad II

===Accession and first reign===
[[File:Hunername 138a.jpg|thumb|left|200px|Sultan Murad II at archery practice. ''[[Hünername]]'' (1584-1588), TSMK Hazine 1523]]
Murad's reign was troubled by insurrection early on. The [[Byzantine Empire|Byzantine]] Emperor, [[Manuel II Palaiologos|Manuel II]], released the 'pretender'<ref>Finkel, C., ''Osman's Dream:The History of the Ottoman Empire'', Osman 2005, p. 43, Basic Books</ref> [[Mustafa Çelebi]] (known as Düzmece Mustafa) from confinement and acknowledged him as the legitimate heir to the throne of [[Bayezid I]] (1389–1402). The Byzantine Emperor had first secured a stipulation that Mustafa should, if successful, repay him for his liberation by giving up a large number of important cities. The pretender was landed by the [[Byzantine]] galleys in the European dominion of the sultan and for a time made rapid progress. Many Ottoman soldiers joined him, and he defeated and killed the veteran general [[Bayazid Pasha]], whom Murad had sent to fight him. Mustafa defeated Murad's army and declared himself Sultan of [[Adrianople]] ([[Edirne]]). He then crossed the [[Dardanelles]] to Asia with a large army but Murad out-manoeuvered Mustafa. After which, Mustafa's force defected in large numbers to Murad II. Mustafa took refuge in the city of [[Gallipoli]], but the sultan, who was greatly aided by a [[Genoa|Genoese]] commander named Adorno, besieged him there and stormed the place. Mustafa was taken and put to death by the sultan, who then turned his arms against the Roman emperor and declared his resolution to punish the [[Palaiologos]] for their unprovoked enmity by the capture of [[Constantinople]].

Murad II then formed a new army called [[Azeb]] in 1421 and marched through the Byzantine Empire and [[Siege of Constantinople (1422)|laid siege to Constantinople]]. While Murad was besieging the city, the Byzantines, in league with some independent [[Turkic peoples|Turkish]] [[Anatolia]]n states, sent the sultan's younger brother [[Küçük Mustafa]] (who was only 13 years old) to rebel against the sultan and besiege [[Bursa]]. Murad had to abandon the siege of Constantinople in order to deal with his rebellious brother. He caught Prince Mustafa and executed him. The Anatolian states that had been constantly plotting against him &mdash; [[Aydinids]], [[Germiyanids]], [[Menteshe]] and [[Beylik of Teke|Teke]] &mdash; were annexed and henceforth became part of the [[Ottoman Sultanate]].

Murad II then declared war against [[Republic of Venice|Venice]], the [[Karamanid]] Emirate, [[Serbia]] and [[Hungary]]. The Karamanids were defeated in 1428 and [[Republic of Venice|Venice]] withdrew in 1432 following the defeat at the second [[Siege of Thessalonica (1422–1430)|Siege of Thessalonica]] in 1430. In the 1430s Murad captured vast territories in the [[Balkans]] and succeeded in annexing Serbia in 1439. In 1441 the [[Holy Roman Empire]] and [[Poland]] joined the [[Serbia]]n-Hungarian coalition. Murad II won the [[Crusade of Varna]] in 1444 against [[John Hunyadi]].