Exiled prince comes back as a fearsome mercenary and takes back his rightful place and builds a great kingdom.
Exiled prince comes back as a fearsome mercenary and takes back his rightful place and builds a great kingdom.
That sounds very much like The Rise of Azkoval by Jay Cantrell, currently still being written (he says hoping not to be a hostage to fortune!).
https://storiesonline.net/s/17413/the-rise-of-azkoval
https://storiesonline.net/a/Jay_Cantrell
In "Always on Guard" his "rightful place" was the one he had no intention of returning to, apart from one little military expedition lasting around a week.
Agreed, but he was exiled, set up his own kingdom, went on a major mercenary rampage to right wrongs, went home, and returned briefly to his original home. I remember he caused panic on his returning since it was assumed that he was a force from the kingdom that did the wrongs he righted. Apart from not retaking his rightful place (as he'd carved out a new rightful place already, which he returned to) it fits pretty well, and IIRC his father's kingdom becomes a supplicant to his new one.
Just as an aside, I thought his behaviour in Umbria - including massacres of civilians - was similar to Genghis Khan's, although not as bad as Tamerlane/Timur.