[Diplomacy related?] AI Lords are loyal despite having no fiefs

[Youbar]

I'm not sure if this is because I have the diplomacy mod or not.
I've reduced the nords to a single town: Sargoth.
King Ragnar owns Sargoth and one village, with the remaining two villages divided between twelve lords. This has been the case for nearly 100 in-game days.
The next thing you know, while I'm overstretched and at war with the Vaegirs, the Nords declare on me. This wouldn't be an issue for me usually, but I suddenly see a marshal leading 1.5k troops straight to Tihr to take it back. To make things worse, I've spoken with my Chancellor and all but one lord is completely devoted to King Ragnar.
Why? What reason do they have to be devoted towards him? Why would you serve a king who can't give you any land? I've checked his kingdom policies, and they don't provide any +1/2/3/etc relationship modifiers to his vassals.
It's frustrating beyond belief, to the point where I want to tweak King Ragnar's relations with his vassals to a negative.

 

[KingofallSwadia]

I would guess its the mod.  On vanilla when a faction is losing fiefs left and right so go the vassals.  I am using a mod right now and am noticing the fairly usual occurrence in vanilla of disgruntled vassals showing up in my castles barely happens at all now.  I've even offered fiefdoms to vassals in a faction with only one crap city and the Rhodocks who own half the map ready to take it and they still won't leave. 

 

[Sequester]

Not only that. The number of troops is way too high. A king may have a couple of hundred troops after staying out of battle for a long time. His vasalls without fiefs should have no more than 50 soldiers each. So unless he has 20 vasalls left there should never be so many Nords.

 

[Youbar]

I figured out most of the problem.
After managing to finish off the Nords and Vaegirs and turn to finish off the Sarannids, I noticed that whenever I assigned a fief I'd lose relations with only ten or so lords out of my forty.
I looked into it a bit more and I discovered that it seemed my relations had locked with my older vassals, from the grumbling/suspicious ones to the devoted.
I'm guessing that Diplomacy is causing this, and that as a result those vassals I said were devoted had been with the ruler long enough to lock relations, and that the trigger for them to degrade relations again would require you to take their faction's last fief.
I'm not sure if this is WAD or a bug, and if this relation lock would be triggered by certain domestic policies or that the game just isn't showing the relation updates for whatever reason.

 

[barlmoro]

im not sure why the first problem occurs (loyal lords staying with nearly dead faction), but i can probably answer the no relation update. i cant remember where i read this, but once lords realize only your faction holds land (other factions are in a coma), theyll stop hating on you. after playing through a few mods with diplomacy (whichs most i think) and you have most of the map, they finally realize that staying fiefless in your kingdoms the best chance theyve got to get a fief of their own.