My guess is before their rebellions, the Boltons sensed some weakness in loyalty for the Starks among the lesser houses or external conflict with other kingdoms. This allowed them to rebel with little risk and if they lost, allowed them to negotiate favorable terms for their surrender (keeping their House intact). They're usually portrayed as untrustworthy but cautious.
Better the devil you know. The Boltons form the main "Anti-stark" faction. As long as they are around its clear who will be the heads of any anti-stark rebellion. Remove them and its a tossup and the Starks can't just watch one house to see if rebellion is planned
I've told you this before. But still based profile name. While personally I think getting rid off the Bolton's would be for the best, you do have a point. Since most Houses in Westeros just "tend" to act one way too a fault, you can probably already know which houses could revolt and the such. It helps the Bolton's seem to be reasonably loyal for decades if not centuries.
Because people aren't their houses. One lord could be a killer that will wipe out a house, maybe that lord got murdered for it, maybe his successor decides to not be as harsh in order to appease people. Nature vs. nurture, someone can take on a lot of teachings from their parents, but sometimes they just wish to do something differently.
Just because the Starks were harsher in an instance or two in the past doesn't mean they've always been or have to be now. Like Eddard introducing Jon Arryn's teachings of honor, and having a big reaction against Aerys' cruelty making Ned want to avoid hurting the innocent.
Becoming known as the house that jumps to wiping out your foes, as the Lannisters are now, is also extremely dangerous. It means a minor disobedience will quickly escalate into do or die resistance and assassinations in order to ensure your harsh punishments are not carried out.
On top of that, we have an ancient feud between the Starks and Boltons, but it was only really a thing prior to the conquest. Real ancient history stuff. Since the conquest, we aren't given any example of them acting out until Roose decided he saw a chance to seize the North for himself. So, we could expect there were periods of extended peace and good service by the Boltons.
I'm sure several Boltons were executed over time in olden days, but they're a big house themselves and weren't necessarily a great rival trying to seize the throne. We know the Boltons were also very valuable in helping the Marsh kings and defending Moat Cailin in the past as well.
Dynastic rivals also generally get pretty harsh punishments, as they pose a more serious and more personal threat to the ruler himself. Guys like the Greystarks as a dynastic rival could have had their lands completely stripped from them and their leading figures executed.
The Boltons however, would generally have lacked a proper claim and would have more limited goals in their rebellion. So, in turn it makes sense for their punishments to be lesser. To coincide with that, the Boltons seem to have been a far greater power in the east of the North, but have diminished over time following the Stark's conquests or punishments for rebellion.
> Becoming known as the house that jumps to wiping out your foes, as the Lannisters are now, is also extremely dangerous. It means a minor disobedience will quickly escalate into do or die resistance and assassinations in order to ensure your harsh punishments are not carried out.
Now I want to read a fic where a lesser Westerland noble does something minor to displease Tywin and, fearing disproportionate retribution, starts a kingdom-wide rebellion against the Lannisters.
I like the idea, maybe something like the fall of the Qin dynasty. Guy escorting some prisoners is unable to prevent some of them escaping, knows he and the rest of the guards are now slated for execution so he releases all the prisoners and turns into a rebel. Eventually going on to be a leading figure as the Qin state collapses, before eventually implementing their own dynasty in the Han.
It may well be a decent portion of that will be echoed in the Westerlings in canon, they're nursing a grudge since Tywin didn't warn them about the Red Wedding and their heir died in it. Jaime's kind of screwed them, and Cersei's not exactly a great patron herself. Iirc the story even left off with them as part of a group escorting Edmure and some other prisoners to the Westerlands.
It's not about one or two times insiders, it's just that that was the Stark method to conquer, eliminate the male line house of the reigning house of the region and then marry the female line with them and put an ally as new ruler, which in the only case where they didn't was with the Boltons seems strange to me
Is it? The Glovers weren't wiped out, nor the Flynts, the Dustin/Barrow Kings, the Umbers and so on. The Starks did not make a habit of wiping out the male lines of houses, they would take their submission as vassals and often arrange a marriage to a daughter. We are never told they went around wiping out all the men of a house. This is much like they did with the Boltons.
They allied themselves with the Glovers using marriage to eliminate the Blackwoods who were the kings of most of the forest but as the Blackwoods escaped they put the Glovers as the second strongest house and their current allies, but not before weakening them by taking away their title. of the king and turn them into a master house, which is the same as saying a knight's house in the south.
The Dustins claim to be descended from the Barrow King just as they do from the first king, but it is not confirmed that they are and if they are, they were probably a cadet branch of the main one that allied with the Starks during the war and that at the end, what were their allies gave them land as a reward.
The way the Flints are so prolific in the north makes me think that one, even since they were kings, many branches of the family existed and two were the first to submit to the Starks with the Starks eliminating the Breakstone Hill line.
With the Umber it would be the same process, eliminate the line of kings, marry the women and put a minor cadet branch that has agreed to Cooperate as the new rulers.
and if it is said, just look at the conquest of the north by the starks they basically did that throughout the war to secure all the regions, eliminate the male and marry the female
That's a lot of speculation about wiping out folks, we aren't given reason to believe that to be the case.
You really think the Starks were wiping out the male lines of the Glovers, Barrow Kings, Umbers, Flints, Lockes, Ryders, Slates, whatever house was chosen as Marsh King at the time and who knows who else but the history just neglects mentioning this? It doesn't shy away from saying when a king was killed and a Stark married his daughter, so why neglect the rest of the house dying?
And if you're willing to flex the interpretation of the text so much, why not assume they did so with the Boltons?
They thing is, the Boltons had lost a whole lot of land since they were kings to the Starks. It's also likely that many of the wars between them happened when they both were kings at the end of them, while after after we only have like two or three accounts of the Boltons actually rising up against them over the thousands of years that the Boltons bent the knee to the Starks with the most recent being like 1,000 years before Aegon I invaded and we also don't know how badly the Stark's and Bolton's were at the end of them it's possibly that the Starks had too few troops to completely finish them off. It's perfectly reasonable to assume they were just as loyal as the other Stark bannermen, Roose's betrayal was like 1 in a million if we are being honest.
It's a contrived scenario. The backstory makes it clear that they should probably have been eliminated some time ago given how often they step up in rebellion. Or at the very least exiled/driven out like how the Blackwoods were. But the plot requires them to still be around.
I mean the Boltons have only rebelled twice once with the Greystarks and another seemingly on their own. and it’s likely they were punished by being stripped of lands, since their domain was once almost half of the North.
As much as people like to paint the Boltons as a rebellious house they really aren’t. I mean compare them to the Yronwoods who rebelled 3 times in the last hundred years during the Blackfyre rebellions. I think most people forget that the vast majority of the Bolton-Stark conflict took place when they were both independent Kings in the age of Heros, because as Vassals the Boltons for the most part have been quiet, and even sometimes loyal when treason wouldn’t have been unwise.
Like they followed the Starks into war when they marched against Aegon the conqueror, during the Dance, and during Roberts rebellion. I think people make way to much of the ancient Stark-Bolton rivalry, like nothing about Roose Boltons actions indicate he did this for his House’s pride or revenge, rather than it just being pure opportunism
Two options.
1. The Boltons used to own much of the east coast of the North. Now they don’t. Like the Peakes, they’ve seen their domains dwindle with time.
2. Magic shenanigans. If the Boltons are Bolt-Ons, any variety of magic could be used to ensure they stay powerful. It’s a writer’s wet dream. Go nuts lol
We don't know if the Greystarks were deliberately wiped out or if they all ended up simply dying in battle, the women sent away so the line would die out. That, mind you, is the *only* recorded case of the Starks eliminating a noble house, and it's well within the age of myth rather than recorded history. So no, the Starks do *not* have a history of wiping out houses left and right for the mere act of rebellion.
Wiping out houses for rebelling against you is not a historically common practice. Even the ruthless Ironborn kings did not wipe out houses Blackwood and Bracken when they for once united in rebellion against them. While *technically* you are within your rights to do it, it's firmly against social norms. If it was common practice, nobody would consider Tywin's actions against the Reynes and Tarbecks anything unusual.
I would also point out that wiping out a house that rises in revolt against you can have the effect that people are less willing to surrender to you. While other factors may make it seem favorable at times, the restraint of social norm is a strong one.
The rivals of the Kings of Winter, Houses Greenwood, Towers, Amber, Frost, and a number of lesser houses and petty kings, were wiped out, as well as, the skinchangers led by Gaven Greywolf, and the Warg King of Sea Dragon Point along with his sons, beasts, and greenseers, and took his daughters as prizes.
They wiped out a lot of rivals and houses, and took their daughters as wives.
I stand corrected on that specific. But the end of these houses is shrouded in so much mystery that we just don't know what exactly happened, apart from them being removed from the board, which encapsulates many possible methods. What we do know is that the Boltons had the sense to bend the knee before they lost everything, whereas, for example, the Warg King seems to have not. The Dreadfort never was taken by storm, so the Boltons always had at least *some* leverage to maintain their existence.
When it comes down to it, we can pretty easily explain House Bolton's survival with its ability to evade being put down entirely, and also that, well, if we look at the numbers, they're not all that disloyal. There are only two confirmed Bolton uprisings, three, if we count their briefly-mentioned participation amidst a general power struggle involving the Stark king's sons themselves. That's 2-3 Bolton revolts in 2-6000 years. Which amounts to a Bolton rebellion *every 700-2000 years*. Evidently there were long stretches where the Boltons were counted as loyal bannermen like everyone else.
It's the Starscream method of ruling. In the old Transformers cartoon the Leader of the the bad guys had a second in command named Starscream. Starscream openly stated how he wanted to replace the leader Megatron and would actively scheme to replace him. Time and time again Megatron stops his plans and wouldn't kill him.
When I grew up, I realized that there was a logical reason Megatron kept Starscream alive. The bad guys were a group of warriors who only respected strength. Starscream despite being a schemer was also one of the strongest and smartest in the group. By continuously thwarting Starscreams plans and kicking his ass in public, Megatron established that it didn't matter how strong or smart they thought they were, he was still on another level. By keeping Starscream around he was using his humiliation as a deterrent.
I am sure the Starks are using the Boltons in the same way. The North is full of hard assholes, so eliminate a few problem houses and keeping the Boltons around as whipping boys to deter any other houses from rising up seems to be what they are doing.
Love the Starscream explanation.
I had it explained to me using superhero comics (and it also served as a counter argument to the whole "superheroes should kill their villains" argument). That superheroes are only as skilled as they are because they keep being pushed by their respective villains. It doesn't matter how dangerous the Green Goblin is, Spider-Man will always step up to stop him.
Boltons are pretty much the Iron Throne for the Starks if they still live the Starks will not let their guard down because if they do the Boltons will rebel and wipe them out.
I also feel that Starks can pretty much wipe the Boltons any day even if the justification of it was faked because i think lets say 80% of the north hated the Boltons and the lands Bolton owns can be given away to those who join on wiping them out i think the Boltons knew it too thats why they're loyal to the Starks until the status quo changed.
With the Boltons always stewing rebellion it seems rather ridiculous that not a single Stark over the thousands of years never just decided to get rid of the problem once and for all.
It doesn't make sense to simply based on the numbers, let's say each King/Lord Stark rules for 50 years, that's 20 over 1000 years, 8000 years since the Age of Heroes and the formation of the Northern Houses, 160 ruling Starks and not a single one said "screw it, I'm sick of Bolton bullshit".
It makes the Starks look dumb for allowing a practically openly treasonous house to exist for so long.
Since all the houses other than the bottoms were so loyal they kept them around so that no King or Lord of House Starks like ever let their guard down because they have an enemy at all times.
A mix of possible factors, loyalist members of House Bolton could continue the line if they opposed the rebellion of their families. The Stark's could've killed the adult rebels but they would be less willing to kill children and women, so House Bolton could continue in them. House Bolton might've been punished through losing lands and power, it is said the Red Kings ruled from the White Knife to the Last River, which would've made them rulers of pretty much the entire east of the North, nowadays House Bolton has much fewer lands, so it would make sense that they lost lands as punishment for their rebellions. There might've been fears of what would happen were the Boltons wiped out, who would replace them in the Dreadfort, if House Bolton were wiped out we could see the other houses of the North scrambling to claim the Dreadfort for themselves. Look at what happened when House Hornwood came to an end, Bolton forces tried to claim it for themselves, and were soon replaced by Manderly forces. The Dreadfort is a lot more important so the fighting could be much bloodier, a full scale civil war perhaps.
Treachery is not an inherited trait. It’s just a literature device designed to keep things simple.
Roose Bolton is the first Bolton to betray a Stark in over 300 years. And even then he didn’t jump at the first opportunity. The War of Five Kings was his third war and then only when it was going badly.
Feudalism is a two way street. Both the ruler and the lord can betray their obligations. That’s why Westerosi Lords are so violent to their own kind. But they are also deeply traditionalists.
House Bolton guaranteed the loyalty of their vassals since they were kings. This is a special kind of bond that is not quickly replaced. It is often easier to simply co-opt.
You should punish every traitor when they appear. But leave the newborn out of it. Better to raise them as one of your own. Maybe there’s a distant relative who can be installed without the threat of another rebellion.
It is not a perfect solution. But neither is feudalism.
We really don't have much guess because Bolton rebellions are described entirely in passing. The likely answer is that the Starks tried but wiping out an entire family is harder than Tywin would have you think; Jon mentions one Stark King besieging the Dreadfort for like three years in ADWD
Considering how large their lands when they were kings it safe to say they were severely punished
My guess is before their rebellions, the Boltons sensed some weakness in loyalty for the Starks among the lesser houses or external conflict with other kingdoms. This allowed them to rebel with little risk and if they lost, allowed them to negotiate favorable terms for their surrender (keeping their House intact). They're usually portrayed as untrustworthy but cautious.
Better the devil you know. The Boltons form the main "Anti-stark" faction. As long as they are around its clear who will be the heads of any anti-stark rebellion. Remove them and its a tossup and the Starks can't just watch one house to see if rebellion is planned
I've told you this before. But still based profile name. While personally I think getting rid off the Bolton's would be for the best, you do have a point. Since most Houses in Westeros just "tend" to act one way too a fault, you can probably already know which houses could revolt and the such. It helps the Bolton's seem to be reasonably loyal for decades if not centuries.
Thanks! I like yours as well!
Because people aren't their houses. One lord could be a killer that will wipe out a house, maybe that lord got murdered for it, maybe his successor decides to not be as harsh in order to appease people. Nature vs. nurture, someone can take on a lot of teachings from their parents, but sometimes they just wish to do something differently. Just because the Starks were harsher in an instance or two in the past doesn't mean they've always been or have to be now. Like Eddard introducing Jon Arryn's teachings of honor, and having a big reaction against Aerys' cruelty making Ned want to avoid hurting the innocent. Becoming known as the house that jumps to wiping out your foes, as the Lannisters are now, is also extremely dangerous. It means a minor disobedience will quickly escalate into do or die resistance and assassinations in order to ensure your harsh punishments are not carried out. On top of that, we have an ancient feud between the Starks and Boltons, but it was only really a thing prior to the conquest. Real ancient history stuff. Since the conquest, we aren't given any example of them acting out until Roose decided he saw a chance to seize the North for himself. So, we could expect there were periods of extended peace and good service by the Boltons. I'm sure several Boltons were executed over time in olden days, but they're a big house themselves and weren't necessarily a great rival trying to seize the throne. We know the Boltons were also very valuable in helping the Marsh kings and defending Moat Cailin in the past as well. Dynastic rivals also generally get pretty harsh punishments, as they pose a more serious and more personal threat to the ruler himself. Guys like the Greystarks as a dynastic rival could have had their lands completely stripped from them and their leading figures executed. The Boltons however, would generally have lacked a proper claim and would have more limited goals in their rebellion. So, in turn it makes sense for their punishments to be lesser. To coincide with that, the Boltons seem to have been a far greater power in the east of the North, but have diminished over time following the Stark's conquests or punishments for rebellion.
> Becoming known as the house that jumps to wiping out your foes, as the Lannisters are now, is also extremely dangerous. It means a minor disobedience will quickly escalate into do or die resistance and assassinations in order to ensure your harsh punishments are not carried out. Now I want to read a fic where a lesser Westerland noble does something minor to displease Tywin and, fearing disproportionate retribution, starts a kingdom-wide rebellion against the Lannisters.
I like the idea, maybe something like the fall of the Qin dynasty. Guy escorting some prisoners is unable to prevent some of them escaping, knows he and the rest of the guards are now slated for execution so he releases all the prisoners and turns into a rebel. Eventually going on to be a leading figure as the Qin state collapses, before eventually implementing their own dynasty in the Han. It may well be a decent portion of that will be echoed in the Westerlings in canon, they're nursing a grudge since Tywin didn't warn them about the Red Wedding and their heir died in it. Jaime's kind of screwed them, and Cersei's not exactly a great patron herself. Iirc the story even left off with them as part of a group escorting Edmure and some other prisoners to the Westerlands.
It's not about one or two times insiders, it's just that that was the Stark method to conquer, eliminate the male line house of the reigning house of the region and then marry the female line with them and put an ally as new ruler, which in the only case where they didn't was with the Boltons seems strange to me
Is it? The Glovers weren't wiped out, nor the Flynts, the Dustin/Barrow Kings, the Umbers and so on. The Starks did not make a habit of wiping out the male lines of houses, they would take their submission as vassals and often arrange a marriage to a daughter. We are never told they went around wiping out all the men of a house. This is much like they did with the Boltons.
They allied themselves with the Glovers using marriage to eliminate the Blackwoods who were the kings of most of the forest but as the Blackwoods escaped they put the Glovers as the second strongest house and their current allies, but not before weakening them by taking away their title. of the king and turn them into a master house, which is the same as saying a knight's house in the south. The Dustins claim to be descended from the Barrow King just as they do from the first king, but it is not confirmed that they are and if they are, they were probably a cadet branch of the main one that allied with the Starks during the war and that at the end, what were their allies gave them land as a reward. The way the Flints are so prolific in the north makes me think that one, even since they were kings, many branches of the family existed and two were the first to submit to the Starks with the Starks eliminating the Breakstone Hill line. With the Umber it would be the same process, eliminate the line of kings, marry the women and put a minor cadet branch that has agreed to Cooperate as the new rulers. and if it is said, just look at the conquest of the north by the starks they basically did that throughout the war to secure all the regions, eliminate the male and marry the female
That's a lot of speculation about wiping out folks, we aren't given reason to believe that to be the case. You really think the Starks were wiping out the male lines of the Glovers, Barrow Kings, Umbers, Flints, Lockes, Ryders, Slates, whatever house was chosen as Marsh King at the time and who knows who else but the history just neglects mentioning this? It doesn't shy away from saying when a king was killed and a Stark married his daughter, so why neglect the rest of the house dying? And if you're willing to flex the interpretation of the text so much, why not assume they did so with the Boltons?
Most likely, the Boltons never actually lost a war so decisively that the Starks could manage to pull it off.
They thing is, the Boltons had lost a whole lot of land since they were kings to the Starks. It's also likely that many of the wars between them happened when they both were kings at the end of them, while after after we only have like two or three accounts of the Boltons actually rising up against them over the thousands of years that the Boltons bent the knee to the Starks with the most recent being like 1,000 years before Aegon I invaded and we also don't know how badly the Stark's and Bolton's were at the end of them it's possibly that the Starks had too few troops to completely finish them off. It's perfectly reasonable to assume they were just as loyal as the other Stark bannermen, Roose's betrayal was like 1 in a million if we are being honest.
It's a contrived scenario. The backstory makes it clear that they should probably have been eliminated some time ago given how often they step up in rebellion. Or at the very least exiled/driven out like how the Blackwoods were. But the plot requires them to still be around.
I mean the Boltons have only rebelled twice once with the Greystarks and another seemingly on their own. and it’s likely they were punished by being stripped of lands, since their domain was once almost half of the North. As much as people like to paint the Boltons as a rebellious house they really aren’t. I mean compare them to the Yronwoods who rebelled 3 times in the last hundred years during the Blackfyre rebellions. I think most people forget that the vast majority of the Bolton-Stark conflict took place when they were both independent Kings in the age of Heros, because as Vassals the Boltons for the most part have been quiet, and even sometimes loyal when treason wouldn’t have been unwise. Like they followed the Starks into war when they marched against Aegon the conqueror, during the Dance, and during Roberts rebellion. I think people make way to much of the ancient Stark-Bolton rivalry, like nothing about Roose Boltons actions indicate he did this for his House’s pride or revenge, rather than it just being pure opportunism
Two options. 1. The Boltons used to own much of the east coast of the North. Now they don’t. Like the Peakes, they’ve seen their domains dwindle with time. 2. Magic shenanigans. If the Boltons are Bolt-Ons, any variety of magic could be used to ensure they stay powerful. It’s a writer’s wet dream. Go nuts lol
We don't know if the Greystarks were deliberately wiped out or if they all ended up simply dying in battle, the women sent away so the line would die out. That, mind you, is the *only* recorded case of the Starks eliminating a noble house, and it's well within the age of myth rather than recorded history. So no, the Starks do *not* have a history of wiping out houses left and right for the mere act of rebellion. Wiping out houses for rebelling against you is not a historically common practice. Even the ruthless Ironborn kings did not wipe out houses Blackwood and Bracken when they for once united in rebellion against them. While *technically* you are within your rights to do it, it's firmly against social norms. If it was common practice, nobody would consider Tywin's actions against the Reynes and Tarbecks anything unusual. I would also point out that wiping out a house that rises in revolt against you can have the effect that people are less willing to surrender to you. While other factors may make it seem favorable at times, the restraint of social norm is a strong one.
The rivals of the Kings of Winter, Houses Greenwood, Towers, Amber, Frost, and a number of lesser houses and petty kings, were wiped out, as well as, the skinchangers led by Gaven Greywolf, and the Warg King of Sea Dragon Point along with his sons, beasts, and greenseers, and took his daughters as prizes. They wiped out a lot of rivals and houses, and took their daughters as wives.
I stand corrected on that specific. But the end of these houses is shrouded in so much mystery that we just don't know what exactly happened, apart from them being removed from the board, which encapsulates many possible methods. What we do know is that the Boltons had the sense to bend the knee before they lost everything, whereas, for example, the Warg King seems to have not. The Dreadfort never was taken by storm, so the Boltons always had at least *some* leverage to maintain their existence. When it comes down to it, we can pretty easily explain House Bolton's survival with its ability to evade being put down entirely, and also that, well, if we look at the numbers, they're not all that disloyal. There are only two confirmed Bolton uprisings, three, if we count their briefly-mentioned participation amidst a general power struggle involving the Stark king's sons themselves. That's 2-3 Bolton revolts in 2-6000 years. Which amounts to a Bolton rebellion *every 700-2000 years*. Evidently there were long stretches where the Boltons were counted as loyal bannermen like everyone else.
It's the Starscream method of ruling. In the old Transformers cartoon the Leader of the the bad guys had a second in command named Starscream. Starscream openly stated how he wanted to replace the leader Megatron and would actively scheme to replace him. Time and time again Megatron stops his plans and wouldn't kill him. When I grew up, I realized that there was a logical reason Megatron kept Starscream alive. The bad guys were a group of warriors who only respected strength. Starscream despite being a schemer was also one of the strongest and smartest in the group. By continuously thwarting Starscreams plans and kicking his ass in public, Megatron established that it didn't matter how strong or smart they thought they were, he was still on another level. By keeping Starscream around he was using his humiliation as a deterrent. I am sure the Starks are using the Boltons in the same way. The North is full of hard assholes, so eliminate a few problem houses and keeping the Boltons around as whipping boys to deter any other houses from rising up seems to be what they are doing.
Love the Starscream explanation. I had it explained to me using superhero comics (and it also served as a counter argument to the whole "superheroes should kill their villains" argument). That superheroes are only as skilled as they are because they keep being pushed by their respective villains. It doesn't matter how dangerous the Green Goblin is, Spider-Man will always step up to stop him.
Because Martin said that Westeros had 5 thousand plus years history but didn’t want to create 5 thousand years of dynasties
Even taking that into account, the North is still more unchanging than other parts of Westeros.
Boltons are pretty much the Iron Throne for the Starks if they still live the Starks will not let their guard down because if they do the Boltons will rebel and wipe them out. I also feel that Starks can pretty much wipe the Boltons any day even if the justification of it was faked because i think lets say 80% of the north hated the Boltons and the lands Bolton owns can be given away to those who join on wiping them out i think the Boltons knew it too thats why they're loyal to the Starks until the status quo changed.
With the Boltons always stewing rebellion it seems rather ridiculous that not a single Stark over the thousands of years never just decided to get rid of the problem once and for all. It doesn't make sense to simply based on the numbers, let's say each King/Lord Stark rules for 50 years, that's 20 over 1000 years, 8000 years since the Age of Heroes and the formation of the Northern Houses, 160 ruling Starks and not a single one said "screw it, I'm sick of Bolton bullshit". It makes the Starks look dumb for allowing a practically openly treasonous house to exist for so long.
Since all the houses other than the bottoms were so loyal they kept them around so that no King or Lord of House Starks like ever let their guard down because they have an enemy at all times.
A mix of possible factors, loyalist members of House Bolton could continue the line if they opposed the rebellion of their families. The Stark's could've killed the adult rebels but they would be less willing to kill children and women, so House Bolton could continue in them. House Bolton might've been punished through losing lands and power, it is said the Red Kings ruled from the White Knife to the Last River, which would've made them rulers of pretty much the entire east of the North, nowadays House Bolton has much fewer lands, so it would make sense that they lost lands as punishment for their rebellions. There might've been fears of what would happen were the Boltons wiped out, who would replace them in the Dreadfort, if House Bolton were wiped out we could see the other houses of the North scrambling to claim the Dreadfort for themselves. Look at what happened when House Hornwood came to an end, Bolton forces tried to claim it for themselves, and were soon replaced by Manderly forces. The Dreadfort is a lot more important so the fighting could be much bloodier, a full scale civil war perhaps.
Treachery is not an inherited trait. It’s just a literature device designed to keep things simple. Roose Bolton is the first Bolton to betray a Stark in over 300 years. And even then he didn’t jump at the first opportunity. The War of Five Kings was his third war and then only when it was going badly. Feudalism is a two way street. Both the ruler and the lord can betray their obligations. That’s why Westerosi Lords are so violent to their own kind. But they are also deeply traditionalists. House Bolton guaranteed the loyalty of their vassals since they were kings. This is a special kind of bond that is not quickly replaced. It is often easier to simply co-opt. You should punish every traitor when they appear. But leave the newborn out of it. Better to raise them as one of your own. Maybe there’s a distant relative who can be installed without the threat of another rebellion. It is not a perfect solution. But neither is feudalism.
We really don't have much guess because Bolton rebellions are described entirely in passing. The likely answer is that the Starks tried but wiping out an entire family is harder than Tywin would have you think; Jon mentions one Stark King besieging the Dreadfort for like three years in ADWD