Well it depends. If it was a fallen version of Lowblood than it would have to be a story of slaughter. Perhaps Victor could kill the fallen beast king and become a king of corpses himself. (Much like if he were to help Umbral Lowblood.)
With a new generation of praise to follow under his rule and he could even gain the powers that all rulers hold.
But if it's a normal nation such as the current Lowblood it could start as a simple battle with the ruler, this could result as him taking the throne and you could explain how the populus would react to such a thing, even them turning all to beasts as a possible means of rebellion and Victor crafting something to cure that keeps them in line.
And just set Lowblood on a overdrive to an advanced age all under his thumb.
I've been editing my lore a bit. So I've also been thinking about the path the nation can take. So I've been through quite alot of thought.
I would definitely look into souls leif you have the time and just feel like doing so as it'll give you the vibe.
While there's not much iconic sense from the various series there is aspects, like the abyss from the darksouls series, beasthood and hunters from bloodborne.
( incoming: Heavy Lowbloodian lore.)
Read if you wish.
And the linking of the flame is a big factor but it's been twisted so instead of linking the flame it's been spilling the blood of the prior holder of the soul of the first king.
You see in the beginning of the nation the was an ancient great creature that died and bestowed his power to man and woman through soul.
(This causes the vary being of Lowblood to shift around its grave as it causes a creater to form, that's where all rulers are buried.)
This gave humanity power they did not possess prior to take on the other creatures that threatened their kind.
The one holding the most of the creatures soul became the first king.
And when he finally grew to an age where he could barely fight anymore he wished to have one last fight as a sendoff, and the one that could best him would hold the soul and rule over the lands. And this would be how it plays out as a cycle. And yes the soul can inhabit machine even give life to it, a rather sentience that some lack.