It's a random encounter for you to get to know there is an Assassins Guild in the game. It happens always early in the game (so it's somewhat scripted) and later you get the option to join them or destroy them. The player never gets to know who wanted you dead and you can't ask any of the Dark Brotherhood about it. Similarly, why does the Dark Brotherhood want me dead?
The Dark Brotherhood doesn't want you dead - their customers want you dead. The DB simply wants to fulfill their contractural obligations. The fact that you sometimes encounter DB assassins implies that someone has committed the Black Sacrament in an effort to have you murdered.
Likewise, is it worth destroying the Dark Brotherhood? Then don't destroy them. The only benefit is that if you're not going to do the questline, you won't get all those assassins chasing you around Skyrim. Other than that, it's a waste of a good faction questline.
In this regard, is it better to kill or join the Dark Brotherhood?
@TheHT said: You get WAY more stuff if you join, but if you're RPing or whatever then by all means. But you'll obviously will get more loot/money/quests by not destroying one of the main factions. Almost all the items unique to the faction can be looted off the dark brotherhood members once you've killed them.
How do you get the Dark Brotherhood to attack you in Morrowind?
Speak to Matius about the Dark Brotherhood to be directed to Asciene Rane in the Grand Council Chamber in Ebonheart. Mention Transport to Mournhold to Rane to be teleported to the Royal Palace in Mournhold. Talk to any Royal Guard or High Ordinator in Mournhold to complete the quest.
Related Question Answers
How do I get rid of my spectral assassin?
If you want to get rid of him, then kill him. Pretty simple. You can even sneak attack him. Who does the Dark Brotherhood want me to kill?
A hooded woman known as Astrid tells you that she is from the Dark Brotherhood and that you owe a debt to them.To repay it, you must simply kill one of the three captives in the shack (to kill one is optional) . Kill all three to impress Astrid if you want. Why does Astrid betray Dark Brotherhood?
However, it turns out that Astrid, fearing that her leadership of the Dark Brotherhood was threatened by the Dragonborn being the new Listener for the Night Mother, betrays him and reports the assassination attempt to the Penitus Oculatus and Maro himself, in return for amnesty and protection of the Dark Brotherhood. What does the Dark Brotherhood give you?
You receive your own set of shrouded armor, which boosts several of the skills most useful to an assassin. The only other source of this armor is named Dark Brotherhood members. You may obtain shrouded robes, shoes, hood, and hand wraps, which yield no armor rating but have other enchantments useful to assassins. What happens if you don't kill Astrid?
Will never take life too seriously. Should you decide to kill off Astrid, you will begin a new quest line to Destroy the Dark Brotherhood. You will also be able to retrieve her unique equipment. As obvious as it might be, you will be unable to further continue the quest line for joining them. Why did Astrid sent an assassin after me?
It's a random encounter for you to get to know there is an Assassins Guild in the game. It happens always early in the game (so it's somewhat scripted) and later you get the option to join them or destroy them. The player never gets to know who wanted you dead and you can't ask any of the Dark Brotherhood about it. Can you be a Jarl in Skyrim?
You cannot become Jarl in the base game. The most you can become is Thane in the holds. As SuperSajuuk said, there's no option for becoming a Jarl in the vanilla versions of Skyrim and it's DLCs. The only way would be downloading a mod enabling that for the PC version of Skyrim. Can you kill Astrid in the shack?
When you are kidnapped by the Brotherhood and brought to the Abandoned Shack, kill Astrid instead of a hostage and this quest will begin. After Astrid's death, travel to any city and speak to a guard. Can you marry Astrid?
Is it possible to marry Astrid in Skyrim? Nope. First of all she is already married and he is essential until he dies in the quest where you destroy the dark brotherhood or when the Pentius Oculatus does. In both of these quests, Astrid dies in them anyway, so you can't keep her husband alive without her dying. Should I kill Cicero or Astrid?
The punishment for breaking the Tenets according to Sithis in Oblivion is expulsion from the Dark Brotherhood or death. This is why you must kill her Cicero is the head of the Dark Brotherhood not her. Most of the time I just kill Astrid in the shack. Should I kill Amaund Motierre?
After collecting the reward, the Dragonborn has the option to kill Motierre. Doing so gives the advantage of collecting a few rare gems from his corpse, as well as possibly receiving an inheritance from him. Should I kill the Dark Brotherhood oblivion?
It is not necessary to kill them to complete the quest, though the Guardian will attack the Hero if they openly assault another Brotherhood member. Can you take down the thieves guild?
Sadly, there is no quest to destroy the Thieves Guild in Skyrim. If your on the PC there is a mod called Destroy the Thieves Guild where you can bring down the guild and Maven (be sure to read the description). Can you get Shadowmere if you kill Astrid?
No. The quest "Destroying the Dark Brotherhood" activates only if you attack Astrid in the Abandoned Hut, before you join the Dark Beotherhood. It is impossible to get Shadowmere or Cicero after that. Can I join the Dark Brotherhood and then destroy it?
You cannot. You're only chance, as stated above, is during "With Friends Like These," in which you must first kill Astrid. So I too regretted joining the Dark Brotherhood and would've much more wanted to destroy them. What happens if you kill Grelod the kind before innocence lost?
PC PS4 If Grelod is killed before starting this quest, the quest will become glitched. When told by Aventus Aretino to kill Grelod she will already be dead, making the quest impossible to complete. Will joining the Dark Brotherhood affect anything?
4 Answers. No, none of the Dark Brotherhood's quests intersect in any meaningful way with any other quest chain. Some targets may have minor 'radiant' quests available, but none are significant in any way. Can I just kill Ulfric Stormcloak?
Only way to kill Ulfric is to join the Imperials. Should I kill Cicero?
He has 500 gold on him as well as his gear. Since you can pickpocket him and receive higher grade gear at the Dawnstar Sanctuary, it is really not lucrative to kill him. If you have completed the quest line for the Dark Brotherhood, and Cicerio is still alive at that point, he will indeed become a Follower. Can you adopt Aventus Aretino?
You can now adopt Aventus Aretino. Speak to him in the Aretino Residence after completing the quest Innocence Lost. IMPORTANT NOTE: Once Aventus is adopted the game treats him just like any other adopted kid. What is the greatest illusion of life?
The Black Door in Dawnstar asks, "What is life's greatest illusion?", to which the correct answer is: "Innocence, my brother." learned during the quest "The Cure for Madness." Is there an end to dark brotherhood forever?
Nope, never ends. It's a radiant quest. Can you still get windshear if you kill Astrid?
Astrid drops Windshear when you kill her in the "Destroy the Darkbrotherhood" quest line. Is it worth joining the Thieves Guild in Skyrim?
The Thieves Guild is the faction that keeps on giving. You may have to do despicable things, like framing poor Brand-Shei, but it's totally worth being a lowlife when the questline rewards you with Nightingale Armor and Chillrend, the amazing leveled glass sword. What race is Astrid Skyrim?
Nord assassin
What happens if you kill Astrid in the abandoned shack?
TIL if you kill Astrid in the Abandoned Shack, you start a Penitus Occulatus quest I would LOVE to see this redone. You kill Astrid, and then find the Sanctuary empty, but with information on all of the members. You then work with Maro to hunt down the rest of them that have gone into hiding. How do you stop the Dark Brotherhood attacks in Morrowind?
After you've been attacked by the assassins at least once, if you talk to Apelles Matius in Ebonheart about the matter, the attacks will stop. Is the Dark Brotherhood in Morrowind?
The Dark Brotherhood was added to The Elder Scrolls III: Morrowind via the The Elder Scrolls III: Tribunal official plug-in, alongside Mournhold. How do I start the tribunal DLC?
Go to Khuul and take a boat to Solstheim. When you get there enter the fort and talk with Captain Carius. Tribunal: Lv up to Lv 6 and then keep resting. Kill the assassin that attacks you, Now go to Ebonheart and speak with Appelles Matius. Where is Apelles Matius in Ebonheart?
You should be able to find her in the Grand Council Chambers here in Ebonheart." transport to Mournhold "Well, that's what you'll need if you're so hell-bent on tracking down these Dark Brotherhood assassins you claim have visited you." 
