The Massacre of the Khalar vezhven was an event in Vaes Dothrak in Essos that took place concurrently with the Liberation of Slaver's Bay, in which Daenerys Targaryen massacred the entirety of the Khalar vezhven and claimed leadership over all Dothraki from Vaes Dothrak.
Queen of Meereen Daenerys Targaryen is taken by a Dothraki horde after her escape from her city. Qhono and Aggo, take her to their Khal, Moro, as a gift. The Khal wants to rape her, but she explains who she is, Khal Drogo's widow. The Khal unbinds her and promises her that she will not be harmed. When Daenerys asks to be escorted back to Meereen in exchange for the promise of one thousand horses for her safe return, Moro's wives tells her that she has to remain in the temple of Vaes Dothrak with the other Khals' widows for the remainder of her days and become a Dosh khaleen.
She later walks with the Dothraki towards Vaes Dothrak and is ushered into the the Temple of the Dosh Khaleen by Khal Moro's bloodriders. The High Priestess of the Dosh Khaleen orders the bloodriders to leave and strips Daenerys naked, giving her a robe which the dosh khaleen wear. As Daenerys puts on her new clothes, she tells the high priestess that she will soon regret what she has done as she was the wife of a great khal, the Queen of Meereen, and the Mother of Dragons. The high priestess retorts that she herself was the wife of a previous Great Khal, Savo. Just as Daenerys thought she would conquer the world at Drogo's side, so did the high priestess think she would conquer the world at Savo's. But Savo was slain, and she joined the dosh khaleen. She is now content, just as Daenerys would be in time, if she is in fact allowed to join them. When Dany expressed confusion, the priestess points out that khaleesi are supposed to return to Vaes Dothrak immediately after their khal's death... but Daenerys went out into the world. She explains that all the khalasars have gathered to decide which cities will be sacked and which tribes will be enslaved, and now they will have to decide what to do with Daenerys for not coming to the dosh khaleen after Khal Drogo died - allowing her to join the dosh khaleen being the best outcome.
Daenerys asks to relieve herself, and the high priestess sends Ornela with her. As they walk, Daenerys learns that Ornela's khal died when she was only sixteen. The pair are interrupted by Jorah Mormont and Daario Naharis, who take the Lhazareen hostage. Daenerys, unsurprised to see them, cancels their plans for escape – they have a slim chance of leaving Vaes Dothrak, let alone getting back to Meereen – and tells them that she has a plan of her own. She asks Ornela if she is willing to help them, calling her Khaleesi (queen) instead of a khaleen (crone). The girl reluctantly agrees.
During the Khalar vezhven, the khals argue about how to deal with Iggo and Aggo's deaths; Khal Moro defuses the situation by reminding them that Ahko was a member of his khalasar, and he does not care about finding the killer if he was stupid enough to get himself killed. Daenerys is then brought in by the two priestesses she befriended before. Moro feels she should join the dosh khaleen, but another khal expresses interest in making her his khaleesi, while another suggests giving her to the Wise Masters in exchange for ten thousand horses.
Daenerys dismisses all of them. She reminds them that her husband, in the same temple in which they all now sit, declared that he would lead a Dothraki army across the Narrow Sea to retake the Iron Throne for his khaleesi, while all they have done since is raid and plunder nearby villages. She declares they are all petty and weak, and none of them are fit to lead the Dothraki - so she will lead them herself.
Daenerys's broad smile deepens at his threats and replies that they won't have to follow her because this is where they will die. She knocks over the braziers at the center of the temple, setting the entire building aflame. The khals desperately attempt to escape the rapidly spreading fire, only to find the temple's only door barred, the bodies of the two khaleen guarding it lying dead outside. Moro tries to confront Dany a final time, but she upends the last brazier on him, completing the conflagration.
As the flames climb higher, the dosh khaleen and khalasars gather in confusion. Eventually, the doors collapse and Daenerys emerges, naked and unburnt. Many of the assembled bows immediately, with the high priestess and the rest of the dosh khaleen following.
While Daenerys flies to Meereen on the back of Drogon, the Dothraki follow on their horses. During the second siege of Meereen, the Dothraki and Daario Naharis arrive before the city's gates and swiftly slaughter the Sons of the Harpy who are executing some of Meereen's inhabitants.
In the books
As Daenerys' storyline in the sixth season has preceded her book storyline, this event has not yet appeared in the books. Although Daenerys has been found by a khalasar, she has not yet been brought to Vaes Dothrak.