Transformation of the Ottoman Empire
Sultan Suleiman I (r. 1520–1566) was the longest-reigning sultan in Ottoman history, but the last years of his reign were characterized by uncertainty over who would be his successor. Suleiman had three sons who could hope to succeed, Mustafa, Bayezid, and Selim. While the latter two were the children of Suleiman's wife Hurrem Sultan, the first was the son of an earlier concubine. Mustafa may have felt that his half-brothers possessed an unfair advantage over him, and thus worked to secure the favor of the military. Perhaps suspecting that Mustafa planned to dethrone him just as his own father had done to his grandfather, Suleiman acted first and in 1553 ordered that Mustafa be executed. The death of Hurrem Sultan in 1558 triggered open conflict between the two remaining candidates, and Selim ultimately emerged victorious. Suleiman further strengthened his son's position by arranging a marriage between Selim's daughter and the influential Sokollu Mehmed Pasha (Grand Vizier 1565–1579). Suleiman died in 1566, while besieging the fortress of Szigetvar in Hungary, bringing Selim to the throne.
Suleiman the Magnificent
Sultan Suleiman's two consorts (Hürrem and Mahidevran) had borne him six sons, four of whom survived past the 1550s. They were Mustafa, Selim, Bayezid, and Cihangir. Of these, the eldest was not Hürrem Sultan's son, but rather Mahidevran's, and therefore preceded Hürrem's children in the order of succession. Hürrem was aware that should Mustafa become Sultan her own children would be strangled. Yet Mustafa was recognized as the most talented of all the brothers and was supported by Pargalı İbrahim Pasha, who was by this time Suleiman's Grand Vizier. The Austrian ambassador Busbecq would note "Suleiman has among his children a son called Mustafa, marvelously well educated and prudent and of an age to rule, since he is 24 or 25 years old; may God never allow a Barbary of such strength to come near us", going on to talk of Mustafa's "remarkable natural gifts".
Hürrem is usually held at least partly responsible for the intrigues in nominating a successor. Although she was Suleiman's wife, she exercised no official public role. This did not, however, prevent Hürrem from wielding powerful political influence. Since the Empire lacked, until the reign of Ahmed I, any formal means of nominating a successor, successions usually involved the death of competing princes in order to avert civil unrest and rebellions. In attempting to avoid the execution of her sons, Hürrem used her influence to eliminate those who supported Mustafa's accession to the throne.