They were more of a trouble than normal hired thugs or dark brotherhood assassins. I didn't kill any Thalmors or do the main quest. Only levelled up doing the bounties from inns and killing creatures in the wildness. A group of Thalmor dogs came at me. Their corpses had a writ of execution...

:-(

And Merry Christmas to you all!

I think these assassins have gone nuts, one of my own assassins attacked me even though I AM the listener ! and there was a letter on him that said Astrid has ordered it , but she's already dead !

Maybe he was dispatched before you became the listener and he just really svcked at tracking you down?

You're right , maybe that's the reason he attacked me .

On my first character, I got Thalmor assassins attacking me when literally the only thing I had done was left Riverwood and done some of the main quest in Whiterun. Hadn't even encountered the Thalmor, but apparently I was their enemy and extremely dangerous. Well, I proved them right, eventually.

I just had the Thalmor send an assassin after me as well. I'm in Riften when suddenly I hear about six or seven NPCs shouting their battle cries - "Skyrim is for the Nords!" and "You won't get away!", that kind of thing - so I mosey over to see what's going down. Looks they've all ganged up to take down this random Khajiit chick, so I approach her to see if maybe she's a part of a quest or something. Nope! She turns and charges at me, but before she can get in a single blow the blacksmith lands a killer strike. I search her body and, well, would ya lookie here, she's been hired to ghost me. Good to know Riften's got my back in times of need.

In the opening sequence your name is taken before being sent to the chopping block and there is at least one Thalmor present. It could be possible that the assassins were dispatched to assist the Imperials in cleaning up the escaped prisoners from Helgen. If you want to stretch the imagination a little more, the Thalmor are specifically hunting you and not the other prisoners because they want the civil war to continue and it is clear to them that you are not a Stormcloak. Your death would not harm their own cause while still assisting the Imperials with the escapees.

It's the best I could come up with for a valid reason if you need it for role-play purposes.

I've been getting a LOT of love in my game. I've been attacked by Thalmor assassins, necromancer assassins, DB assassins, thugs, and assorted thieves. One group of thugs was actually sent by a hagraven, of all people!

Necromancer Assassins, nice!

Yah, I initially was happy to encounter a few unique khajiit NPC's that wern't drug smugglers/bandits/caravaners - had I found a friend from the motherland?!

...but no, every single one of them eventually tried to kill me. (Two of them were Thalmor sleeper agents, one a thalmor cook... watch the carving knife... and J'zargo gave me a batch of faulty scrolls) - c'mon, where's the love for the lonely khajiit player character.

Hey - don't dismiss those caravaners. They're polite, aren't fond of the Thalmor, and even willing to help take down dragons (suicidal, but I admire their courage).

I don't get it. In my roughly 150 hours of Skyrim and two playthroughs, I've killed every Thalmor patrol I've come across in the wild, cleared out Northwatch Keep, and attacked the Embassy multiple times. I've still never gotten Thalmor assassins after me. What's a guy gotta do to get their attention?

Just keep traveling the roads. Do you break into the Embassy, or just snipe from outside?

Fast travel prevents those types of attacks, although it might add to the chance of dragon attacks, so you have to choose.

You can wander around the country side, especially near the focal points of random events, like near the shack of the old lady mage, sw of Riverwood, and those attacks might randomly occur.

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Of course, you turned the redguard woman to the Alik'r (In my times of need quest). Now, you'll have to be careful because you'll have to deal with Thalmor assassins on a regular basis.