This has happened to me, it's actually pretty funny when they try to attack my level 26 Mage. They're spinning around like an idiot, I'm perma-stunlocking them with 0 cost Destruction spells.

Yeah this random DB attack is based off nothing. I seriously made a new guy, did the golden claw mission, did some woodcutting in riverwood and on my walk to whiterun i was attacked by the assassin when ive literally only met 5 people in the game so far. The only people who could have possibly wanted me dead was either rolof, his aunt or her husband or the two people at the general store, because they were literally the only people ive talked to at this point in the game and then i get attacked by the DB, which makes no sense.

I had to laugh once, I was traveling to a fort for the Stormcloaks. Here comes an Argonian assassin out of nowhere and rushes me. I pulled out my blades and tore him apart. Even though he explicitly told me he would flay me. A few minutes down the same road, here comes a female Argonian this time and I slaughter her the same as the first assassin. Someone must really hate my Bosmer, eh?

If you did the golden claw then you killed many bandits on the way through that dungeon. They have families to you know!

I had the DB assassins in my first game, but in my second I have teams of Thalmar trying to kill me.

It's pretty much left to your imagination why they came after you I guess. I was on my way from Whiterun to Windhelm when I got attacked by a Khajiit assassin, this was like 10 hours in. I hadn't stolen a thing and obeyed all laws so its a bit weird but hey. I think they should not start until you are further in the game, they start way too early its weird.

I never had any DB assassins come after me.

Cool thing I learned though:

The Dark Brotherhood kill because they are told to - the organisation doesn't hate you, but someone does. Doesn't affect your chances of getting in - in fact, if someone could kill ten of my bodyguards, I'd want them to guard me, yknowwhatI'msayin?

Probably they were hired by Altmer.. hence you usually find notes on them about their target. Welcome to the Altmer hater club!

Yeah, the assassin had a note on him. I read it but the name eludes me at the moment.

Come to think of it. I did meet a Thalmor on the road a few hours before that. I exchanged words with the leader of the troupe then the last guard in his caravan had some something to say to me. He accused me of worshiping Talos. I haven't made a decision on whether to worship Talos, or support Ulfuric or the Legion so I just didn't respond to his accusations. This enraged him and he attacked me. I killed him, stripped his body of his weapons and armor then threw his body in the river. I'm thinking the Thalmor guy got to his destination and realized he was one guard short and being since I was probably the last guy he yelled at he figured I must've killed his guard so he ordered my execution through the DB. Is that possible?

Started a new character, up to lvl 14 now, no assassination attempts. My last character got jumped by assassins at least 5 times.

Might be linked to those fugitive guys who run up to you and hand you a stolen item (one possibility of many?). My last character was kind of a goody two shoes so she always gave them back. This character has had that happen once, but she lied to the hunter and said she didn't see anybody. Then she took the item to an enchanting altar and destructed it (it was a shield with resist magic on it).

I haven't been attacked by assassins, but I've been attacked by hired thugs or are they the same thing?

Same function different fighting style.

Oh then I haven't been attacked by assassins that svcks. Are they in the dark brotherhood armor?

Yeah if i remember right, don't think you can take it though.

If you have positive karma, which is almost inevitable early in the game, you will get random hits put out on you. They dont mean much in the long run and arn't mentioned once you join the Dark Brotherhood.

Yeah, sadly, I think this is just a random event. I even read the notes the assassins carry, but there is no clue in them (except to mention the DB themselves) and no quest starts.

That happened to me too... I 'm gonna kill them later

DB works on people hiring mercenaries to take out someone they don't like. DB coming after you is nothing personal, someone just wants you dead.

I think I know why
At the very beginning your character is being transported to helgen for crossing the border
What if DB want you dead for something you've done in another place like cyrodil or hammerfell?
I've been attacked at least 7 times and most of the time I just get on my horse and gallop away. Simply effective but once when crossing the top of a waterfall one came up from behind tried to kill me but was swept over the waterfall and died.
Hehe, these guys are funny