The two great kingdoms of West Asia between 1500 and 1900, the Ottoman Empire and the Safavid Empire, were both monarchies. So they were supposed to be ruled by a single man, the sultan or the shah. He inherited power from his father or his older brother or another male relative. The problem with this system is that you don’t have much control over whether the ruler is a good one. You get whoever you get, whether they’re little babies, or crazy, or sick, or whatever.
The Ottomans solved this problem by putting most of the power into the hands of the wives, mothers, and grandmothers of the sultans. These women were chosen as young women, after they were old enough so you could tell whether they were smart and hard-working. Most of them made good rulers.
Beginning in 1656, though, the Ottomans stopped letting women rule. Instead they gave all the power to the Grand Viziers. That could work too, if the Grand Viziers chose other adult Grand Viziers to succeed them. But unfortunately the Grand Viziers usually chose their own sons, like the Sultans, and with the same bad results.
In the Safavid Empire, viziers and the women at court also fought for control, but here the women lost. But the Safavid Empire never succeeded in uniting everybody into just feeling like Safavids. The Safavid shahs and their viziers were always trying to keep different groups from fighting each other, or from leaving the empire. Some of these groups were the Azerbaijanis, the Afghans, and the Pashtuns. Even today, these groups fight to be independent, and not part of Iran or any other country.