Just to set aside a minor movement in the massive and spectacular evolution of the early Arab caliphates, one can glimpse the psychosocial mechanisms behind the political and economic expansion of the Umayyad Caliphate under Abd al-Malik, whose reign made up a phase of that caliphate.
Legitimacy was generally conferred by hereditary transfers of power, which of course had to be carefully managed even with legitimate heirs lined up. With premature deaths, conflicts could develop over the transfers of power which could lead to civil wars.
Malik was considered to be a "fruitful" leader, fathering some 18 or so children with multiple wives, which would correlate with a period of vigorous expansion, in which the transfer of power was stable more or less, and each successive heir would be looking to continue on the works and gains of his predecessor, so that a steady expansion outward could be effected, denying enemies the breathing room and recovery time afforded by breakouts of civil war.
There does seem to be a dispersal and disintegration with hereditary systems of power, with each successive heir declining in aptitude after the peak of a given "great" leader who fought their way to the top, though this was a common agreed upon method for transferring power legitimately, which is a highly contentious and dangerous process, especially in imperial societies.
We did see variations such as the incredible catapulting of Alexander the Great onto the world stage after succeeding his father, Philip II, who was also considered a great figure and hard to top. Though of course this feat could not be repeated: the legend was that keeping in character, he wryly egged on his successors with some variation of "may the best man win" and so they proceeded to tear apart his newly conquered empire fighting over the power and spoils after he passed.
We saw something similar in the unraveling of the Mongolian empire after the passing of Genghis Khan, which saw incredible territorial gains but which eventually saw succession crises and the splitting of the empire into four khanates that would go their own ways.
Today we see the waxing and waning of hereditary concentrations of power that largely minimize themselves in the public sphere, favoring the formal symbolic participation in the political election and its economic counterpart, the conquest of the market, where regional powers work to capture what they can of the slippery-yet-greedy circulation of global capital.
Succession and expansion is a globally interconnected process of constant and accelerating movement of material transformation.
