Last night something crossed my mind that i never tired so i guess Ill bring it up here. Depending on the side you take in the Civil War there are three possibilities for killing someone that can be met in Sovngarde. Ulfric Storm Cloak, Legate Rikke or Galmar Stone-fist if killed can be met in Sovngarde and i was wondering if Bethesda payed attention to detail here. My question is if you soul trap them, kill them and then go to Sovngarde will they be there? They shouldn't be if their souls are trapped in a soul gem. I can't really think of another way to test the soul trap so let me know if you have information on this.

Hmm, very astute. This also interests me a great deal. Do you plan on testing this yourself? If not I just made a fresh character a few days ago and I suppose I could test it out. But I think their presence in Sovngarde is scripted.

I believe Soul Trap doesn't work on these three, or General Tullius either.
Not 100% on that but i'm pretty sure i remember trying it once, along time ago with my first character who was a mage and sided with the imperials.

If you could then they may come back in 200 years, M'aiq style

That's disappointing if true. Back in the days of Morrowind, you could even soul trap the Tribunal.

If tbey are able to be soul trapped it would be good if they were found wandering the soul cairn.

And Hircine But still.. Suoultrapping a Daedra Prince? Wut?

I have a fresh character i made a week ago but i haven't been playing it much. Last night i picked it up again but a ways away from sovngarde and the Civil War. Ill be sure to post my findings here if someone doesn't already know the end result to my experiment.

It doesnt, at least with Ulfric I know this for certain.
I tend to kill Ulfric with the Soul Tear shout, because that leaves one less body cluttering up the palace. An ash pile is so much less conspicuous, especially when you maneuver your thrall to a somewhat hidden position.
In any case, Ulfric will resist soul trap. Its safe to assume it doesnt work on the other ones either.

I had not even thought about that, I guess thats worth a look as well. Thanks to the stupid vampire attacks however I'm not reinstalling Dawnguard until my new character is 100% ready.