I have shifted to using Dawnbreaker as my primary weapon. The weapon seems to glow in the presence of hostile undead, daedra, and dragon mounds. I also noticed that it glows near the civilians that are camped out in front of Fort Dawnguard. I asked myself why, and looked at their stats at the UESPwiki and they are the class Dremora. I thought it was interesting. Discuss.

Mine lights up all the time, even when I'm alone. Same with that hammer Voldenrung. To me it just looks like the glow from the weapon that's supposed to be isolated to that one point isn't being filtered by the model, so the light emits through it all.

I have found undead not tied to a specific tomb along the road west out of Whiterun with this sword. It is not a coincidence.

I'm not saying it is. For you, it's probably working as intended. But for me, the weapons that have natural lights in them (Dawnbreaker and Voldenrung) usually are glowing completely at all hours of the day and night, even in menus, regardless of where I am or who is nearby. I can be on the Throat of the World and it'll shine like the sun.

It's not isolated to me either:

http://www.uesp.net/wiki/Skyrim_talk:Dawnbreaker#Graphical_Bug.3F

It doesn't glow near undead. (Although this may be what the dev team intended, it doesn't seem to work correctly for the majority.)

Going into a new cell or reloading a save or fast traveling causes Dawnbreaker to glow extremely bright, which is a graphical glitch as far as I know. Taking the weapon off and re-equipping it should remove the bright glow.

I'm pretty sure it's intended, though I still don't know what exactly triggers it. Perhaps the break of dawn?
However, the glow's so bright it kinda hurts my eyes, especially in first person.
A similar glowing effect seems to occur with the Sunhallowed Arrows..

It works.

The thing is like a lightsaber when I'm around undead, I've tested it and it works (for me at least).

My Dawnbreaker always has a slight glow on the hilt, presumably because I'm a vampire so it detects me also, but yeah if I enter a tomb full of draugr the thing lights up like the 4th of July.

So it's totally supposed to do that imo, but it looks like it's a bit glitched for some peeps.

Once I dispatch the undead in the area the glow recedes back to the hilt.

So no one cares those refugees outside Fort Dawnguard are classified as dremora? Anyone tried using a banish spell on them?

The next time I play I am going to cast banish on them. Dawnbreaker seems to work for me fine. It does not glow when I change cells if there are no enemy undead nearby.

Mine seems to glow whenever it wants. I have to unequip and equip it to get rid of its annoyingly blinding shine.

Dremora, weird. I guess just some laziness with the tags is all.