Line of succession to the Ottoman throne

The Ottoman Dynasty had unusual succession practices compared to other monarchies. Those succession practices changed over time, and ultimately the sultanate was abolished in 1922. Later, the House of Osman (Turkish: Osmanoğlu Ailesi) continued the latest succession practice for the head of the family.

From the fourteenth through the late sixteenth centuries, the Ottomans practiced open succession – something historian Donald Quataert has described as "survival of the fittest, not eldest, son." During their father's lifetime, all adult sons of the reigning sultan obtained provincial governorships. Accompanied and mentored by their mothers, they would gather supporters while ostensibly following a Ghazi ethos. Upon the death of the reigning sultan, his sons would fight amongst themselves until one emerged triumphant. A prince's proximity to Constantinople improved his chances of succession, simply because he would hear of his father's death and declare himself Sultan first. A sultan could thus hint at his preferred successor by giving a favourite son a closer governorship. Bayezid II, for instance, had to fight his brother Cem Sultan in the 1480s for the right to rule.

Occasionally, the half-brothers would begin the struggle even before the death of their father. Under Suleiman the Magnificent (1520–1566), strife between his sons Mustafa and Selim caused such internal turmoil that Suleiman ordered the deaths of both Mustafa and another son, Bayezid, leaving Selim the sole heir.

During the reigns of Suleiman and Selim II, the Haseki Sultan (Ottoman Turkish: حسکي سلطان) or chief consort rose to greater prominence. Gaining power within the Imperial Harem, the favourite was able to manoeuvre to ensure the succession for one of her sons. This led to a short period of effective primogeniture. However, unlike the earlier period, when the sultan had already defeated his brothers and potential rivals for the throne in battle, these sultans had the problem of many half-brothers who could act as the focus for rival factions. Thus, to prevent attempts at seizing the throne, reigning sultans practiced fratricide upon accession, starting with Murat I in 1362. Both Murad III and his son Mehmed III had their half-brothers murdered. The killing of all the new sultan's brothers and half-brothers (which were usually quite numerous) was traditionally done by manual strangling with a silk cord. As the centuries passed, the ritual killing was gradually replaced by lifetime solitary confinement in the "Golden Cage" or kafes, a room in the harem from where the sultan's brothers could never escape, unless perchance they became heir presumptive. Some had already become mentally unstable by the time they were asked to reign.

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