In the early period, the Ottomans practiced open succession. During their father's lifetime, all of the adult sons of the reigning sultan would hold provincial governorships. Accompanied and mentored by their mothers, they would gather supporters while ostensibly following a Ghazw ethos. Upon the death of their father, the sons would fight among themselves until one emerged triumphant. How remote a province the son governorned was of great significance. The closer the region that a particular son was in charge of the better the chances were of that son succeeded, simply because he would be told of the news of his father's death and be able to get to Constantinople first and declare himself Sultan. Thus a father could hint at who he preferred by giving his favourite son a closer governorship. Bayezid II, for instance had to fight his brother Cem in the 1480s for the right to rule. Occasionally, the half-brothers would even begin the struggle before the death of their father. During the reign of Suleiman the Magnificent (1520-1566), strife among his sons Selim and Bayezid caused enough internal turmoil that Suleiman ordered the death of Bayezid, leaving Selim II the sole heir.
With Suleiman and Selim, the favourite concubine (haseki) of the Sultan achieved new prominence. Gaining power within the 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 factions that could threaten the sultan. Thus, to prevent attempts upon his throne, the sultan practiced fratricide upon ascending the throne. 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", a room in the Grand Harem from where the sultan's brothers could never escape, unless perchance they became next in line to the throne. Some had already become mentally unstable by the time they were asked to reign.
Mehmet, however, was the last sultan to have previously held a provincial governorship. Sons now remained within the imperial harem until the death of their father. This denied them not only the ability to form powerful factions capable of usurping their father, but also denied them the opportunity to have children while their father remained alive. Thus when Mehmet's son came to the throne as Ahmed I, he had no children of his own. Moreover, as a minor, there was no evidence he could have children. This had the potential to create a crisis of succession and led to a gradual end to fratricide. Ahmed had some of his brothers killed, but not Mustafa (later Mustafa I). Similarly, Osman II allowed his half-brothers Murad and Ibrahim to live. This led to a shift in the 17th century from a system of primogeniture to one of seniority, in which the eldest male within the dynasty succeeded. Thus, Mustafa succeeded his brother Ahmed; Suleiman II and Ahmed II succeeded their brother Mehmed IV before being succeeded in turn by Mehmed's son Mustafa II. Although occasionally a son did succeed his father, just as often, the new sultan was a brother. This continued until the end of the Ottoman Empire in the early 20th century.[1]
Presently the head of the Imperial House of Osman is Ertuğrul Osman V. According to genealogies on the House of Osman there are currently twenty nine people in the line of succession after Ertuğrul Osman V:
