Why did Brynden Tully and Edmure swear fealty to Robb Stark as King of the North and Riverlands?

[jontargaryan]

What did they have to gain by being ruled by the Starks?

[King17]

Not being ruled by the lannisters is a good thing to gain

[thelittledragonthatcould]

We don't know if the Tully's decided that. What we see is a small amount of Northern Lords declare Robb king of the North. Some point after that chapter (maybe seconds, days or weeks) we find out that Robb is king of both kingdoms. We don't know who decided that, though I have a suspicion that the Freys would have been pretty vocal about it.

Now with the Riverlands being on Robb's side they were not going to support the actual King, who's family had attacked them, or either of his uncles claiming to be King. The trouble is that Hoster was too old and weak so I doubt many of the Riverlords would have faith in proclaiming him King.

And then you have the fact that the Riverlands probably has the least amount of difference between its Lords and its Overlord. The Tullys are only rulers because the Targaryens and Baratheons made them so. The Riverlords may not have wanted to proclaim them there betters.

Then there is the fact that the Riverlords would have known that as an independent kingdom they were doomed without support. Making Robb King offers them that support, otherwise he could have left at any time and they would have been incredibly vulnerable.

And finally Robb had a much larger army and had done more for the Riverlords at that stage (rescuing them from Jaime/ accepted a marriage alliance) than the Tullys did.

 

There is basically a lot of reasons. I don't think Edmure had much say in it, and Brynden probably saw more in Robb than he did Edmure.

[Adam Yozza]

4 hours ago, thelittledragonthatcould said:

We don't know if the Tully's decided that. What we see is a small amount of Northern Lords declare Robb king of the North. Some point after that chapter (maybe seconds, days or weeks) we find out that Robb is king of both kingdoms. We don't know who decided that, though I have a suspicion that the Freys would have been pretty vocal about it

Not true. Go back and read the chapter that GreatJon makes his speech in and you'll see that Cat points out that the Riverlords who are there swear fealty to Robb at the same time. "And the river lords were rising too, Blackwood and Bracken and Mallister, houses who had never been ruled from Winterfell, yet Catelyn watched them rise and draw their blades, bending their knees and shouting the old words that had not been heard in the realm for more than three hundred years".

She only mentions 3 by name, but if there were any of the others (Frey, Darry, Vance, Piper and Tully) who didn't declare Robb king at this point, I think they would have been specifically mentioned.

[DMC]

Because NO ONE interrupts Greatjon when he's chanting.

[dbjm]

Because they got caught up in the moment. Greatjon is known for his inspiring speeches 

 

[gregg22]

Let's not forget, In response to Catelyn seizing  Tyrion, Tywin sent his mad dog raping and burning through the Riverlands. This was done to draw Eddard Stark out, so essentially Tywin picked which side House Tully would take on their behalf.

When Ned died the Lannisters were firmly in control of the Crown, to oppose house Lannister now meant rebellion. So they went all in with team Stark.

[Tianzi]

Also, the King of the North was Hoster Tully's eldest daughter's son and being the family of your king is always a good thing.

[Blackfish Tully]

Brynden was no more then a Hedge Knight at that point so he really lost nothing by bending the knee to Robb . As for Edmure once his major lords starting bending the knee to Robb he really had no choice , The Riverlords were declaring open rebellion to the Iron Throne and they would not be to happy if Edmure did not join them . 

[Hugorfonics]

Man was sitting in his fathers castle and his fathers chair. His own bannermen shouted King of the Trident. Stannis spoke truly, Robb conquered the Riverlands.

Also Edmure was in Robb's debt, and of course also, don't piss off Cat

[Chris Mormont]

The Lannisters and thus essentially the Iron Throne was attacking the Riverlands and Rob and his army came to their aid.  Therefore they gain an powerful ally to help you with your common enemy. 

As a bonus, your new king is your nephew

[Raisin' Bran]

Down with the Greatjon and his surprisingly poetic speech.