The meeting adds four more characters to President Donald Trump's complex web of Russian ties, a thorny issue that has dogged the President's first months in office and has prompted formal investigations.
The emails largely confirmed the New York Times story from Monday that said Trump Jr. was told before the meeting that Veselnitskaya was linked to the Kremlin and had damaging information about Hillary Clinton that came from the Russian government. Veselnitskaya denies having Kremlin links.
Donald Trump Jr. says he was first introduced to Veselnitskaya on the day they met in New York, on June 9, 2016.
"When it was suggested that I meet with Donald Trump Jr., I met him in a private situation, it was a private meeting, not related at all to the fact that he was the son of the candidate," Veselnitskaya told CNN's Matthew Chance.
Veselnitskaya is a Russian national who actively lobbied internationally against the Magnitsky Act, a law passed in 2012 that targeted Russians implicated in corruption and human rights abuses.
The law imposed sanctions and banned some Russians from entering the US or using US banking systems.
In a tit-for-tat response to the Magnitsky Act, the Russian government banned the adoption by US families of Russian children.
Veselnitskaya is the founder of a non-governmental organization called the Human Rights Accountability Global Initiative Foundation.
Veselnitskaya also represented a Cyprus-based holding company, Prevezon, which was targeted by US prosecutors under the Magnitsky Act in connection with alleged tax fraud worth $230 million.
In May 2017, Prevezon settled the case
with New York prosecutors after agreeing to pay a $5.9 million. In the settlement, Prevezon and its business associates did not acknowledge any wrongdoing and the government agreed to "release" them all from any future lawsuits in connection with this case.
Finally, Veselnitskaya traveled internationally promoting a documentary film that denounced the Magnitsky Act and the whistle-blower who inspired the legislation, according to media reports.
The New York Times had depicted Veselnitskaya as a Kremlin-linked lawyer, but she has insisted she has no ties to the Russian government. Kremlin spokesman Dmitry Peskov also denies any government links with Veselnitskaya.
In an interview with NBC,
the lawyer confirmed the meeting took place and said it was aimed at discussing US sanctions on Russia.
"I never had any damaging or sensitive information about Hillary Clinton. It was never my intention to have that," Veselnitskaya said.
"It is quite possible that maybe they were longing for such an information. They wanted it so badly that they could only hear the thought that they wanted," she told NBC, according to a translation.
Trump Jr.'s meeting with Veselnitskaya was organized with help from Rob Goldstone. Born in Britain, Goldstone is a former journalist and former marketing executive in the music industry.
He has been a judge in both the Miss Universe
and Miss USA
beauty pageants, according to the websites of those contests, which were owned by Donald Trump for years.
A biography of Goldstone on the websites for both contests lists him as the founder of Oui 2 Entertainment, a company that describes itself on social media
as a "boutique company offering PR, event planning and music management services."
A post on Goldstone's Facebook page on June 9 last year -- the day of the meeting -- shows the publicist checking in to Trump Tower in New York. The post reads: "Preparing for a meeting."
A photograph on his Facebook account shows him at a table with his Azerbaijani pop star client Emin Agalarov, Donald Trump, and several other people. It is unclear when or where the photo was taken, but it was uploaded to Goldstone's account on June 16, 2013, in Las Vegas.
In a statement to CNN, Goldstone said he was asked by Agalarov to help facilitate the meeting between Veselnitskaya and Trump Jr.
Goldstone went on to say "the lawyer had apparently stated she had some information about illegal campaign contributions to the DNC (Democratic National Committee) which she believed Mr. Trump Jr. might find important," he said.
Veselnitskaya denied this in her NBC interview, saying that Trump Jr. had asked her if she had evidence of such contributions.
She told NBC that "it was never my intention to collect any financial records to that end."
Emin Agalarov is a Russian-Azerbaijani pop star and the son of a billionaire oligarch. He lives in Russia, and he sings in Russian and English. He tours under his first name.
He is also a business partner and friend of the Trump family and according to his publicist Goldstone, it was Agalarov who requested the controversial meeting between Trump Jr. and Veselnitskaya be arranged.
CNN contacted Agalarov on Monday requesting an interview. He declined to speak on the subject.
Before his election, President Trump took part in a video clip for one of Agalarov's songs
, in which the pop star daydreams at a board meeting about cavorting with Miss USA beauty pageant contestants, only to be woken up by Trump at the head of the table, in a spoof of "The Apprentice."
"You're just another pretty face, I'm really tired of you. You're fired!" Trump says.
According to Agalarov's website,
he "was the first person ever to persuade Donald Trump to appear in a music video."
That project also dates back to the 2013 Miss Universe pageant, which Trump brought to Moscow with the help of Agalarov and his father.
Another video posted by Emin's official account in 2014 includes birthday wishes from Trump
to the singer.
"Emin, I can't believe you're turning 35," Trump says, sitting at his desk in Trump Tower. "But you're a winner. You're a champ. You're great in real estate. And boy can you entertain."
Days after Trump won the 2016 election, Agalarov boasted about his close ties to the Trump family in an interview with Russian state television.
He said in the November 12, 2016 broadcast that Ivanka Trump was in his office two years earlier to discuss a Trump Tower project in Russia.
"I met many times with the sons, Eric and Donald. We message each other constantly," he added. In addition to his singing career, Agalarov is listed as the first vice president in Crocus Group, a real estate development company led by his father, Aras Agalarov.
The Azerbaijan-born billionaire Aras Agalarov is the patriarch of the family and president of Crocus Group.
In 2013, Putin awarded Agalarov with the Order of Honour
, an accolade presented to Russians whose achievements in their field are extraordinary.
Crocus Group describes itself on its website as a leading development company in Russia with more than 4 million square meters of developed property.
Crocus's stated portfolio includes shopping malls, working as a general contractor for stadiums in the 2018 FIFA World Cup and several Nobu restaurants in Russia.
Crocus was also the organizer of the 2013 Miss Universe pageant in Russia. The Washington Post reported that Agalarov paid Trump between $14 million and $20 million
to stage the pageant in Moscow.
On November 13, 2013, Trump tweeted a message to Agalarov praising the family, with whom he said he had spent a weekend.
Update: This story has been updated to clarify the number of people who appeared in a photograph on Rob Goldstone's Facebook page.