The request came from Rob Goldstone, a music publicist, on behalf of one of his clients, the Russian singer Emin Agalarov. Goldstone wrote that Emin's father, Aras Agalarov — a billionaire developer — had met with a Russian official who offered to provide the Trump campaign with "official documents and information that would incriminate Hillary and her dealings with Russia."
The Agalarovs know the Trumps from the Miss Universe pageant, which was held at one of the Agalarovs' properties near Moscow in 2013. However, the extent of that relationship has recently come under scrutiny.
Luckily, there is a lot of public information put out by the parties themselves to help inform our understanding of these relationships, so let's take a look.
So who are Aras and Emin Agalarov, the Russians mentioned in Don Jr.'s emails?
The Agalarovs are one of Russia’s richest families, with patriarch Aras worth around $2 billion, according to Forbes. The portfolio of their development company, Crocus Group, includes concert halls, shopping centers, restaurants, and residential complexes.
Emin — the pop star son — also serves as executive vice president at Crocus.
In the aftermath of the revelations, the Trumps and the Agalarovs have said that they don't know each other or Goldstone well.
In the statement Trump Jr. tweeted Tuesday along with the screencaps of his emails with Goldstone, he described Emin as "a person I knew from the 2013 Miss Universe Pageant near Moscow." He added that "Emin and his father have a very highly respected company in Moscow."
In a Fox News interview later on Tuesday, Trump Jr. said that Emin was a singer who performed at Miss Universe 2013 and at a 2014 golf championship at the Trump property in Doral, Florida.
"I met him through that, through the golf course. I wasn't even at the Miss Universe pageant, but I met him throughout there, so I had a casual relationship [with him]," he said.
Aras Agalarov, meanwhile, denied having a relationship with Donald Trump Jr. in an interview Wednesday morning with Radio Business FM, a Russian station.
"I don't know [Trump Jr.]. Emin knows him," he said. "We put on Miss Universe, and contacts took place there."
He also said that he "didn't really know" Goldstone.
Emin Agalarov has yet to comment on his relationship with the Trump family, but in an interview with Forbes in February, he said that he and his father had recently been in contact with the Trump family.
"As soon as Mr. Trump got elected, we sent congratulation letters, to which they replied, and we exchanged texts," the Russian pop star said.
However, a look through social media posts by the Agalarovs and Goldstone going back three years shows a more extensive relationship. For example, here's Emin wearing a "Make America Great Again" hat in an Instagram post from Feb. 15.
Also, both Emin and Aras posted old photos of themselves with Trump on Inauguration Day.
So what is the truth? As with many things involving the Trumps and Russia, it's hard to tell. But we're going to try!
Late 2012: Emin decides to relaunch a career in music and flies to Los Angeles to make a music video for his debut single, "Amor."
"The story dates all the way back to 2012 or 2013, I think, when I was filming a video for my new single, which was called 'Amor,' and me and my manager wanted to find the most beautiful woman — model — in the world that we could," Emin said in an interview with Forbes in February about his relationship with Trump and the Trump family. "At the time, we figured we should reach out to the Miss Universe organization and contact the current Miss Universe."
Emin and his manager — yup, Goldstone — were able to get Miss Universe 2012 Olivia Culpo to star as his love interest in the music video.
March 7, 2013: Emin posts a picture of himself and Goldstone at the Miss Universe Organization in New York City.
In the Forbes interview, Emin said that he and his manager formed a good relationship with the Miss Universe organization and its head, Paula Shugart, after filming his music video.
During one of their dinners, he said, Shugart said that the company had wanted to take the contest to Russia for a while. And at some point, Emin suggested that the organization check out his family's venue, Crocus City Hall.
From here, reports vary.
In the Forbes interview, Emin said that Shugart said the organization had a lot of debts, which was apparently a factor in choosing a country and a venue. But a Miss Universe Organization spokesperson denied that debt was discussed.
In an interview with Russian news outlet RIA Novosti in September 2013, Emin said that the Trump team had trouble finding state support (and funding) for the pageant in Russia. However, he ran the numbers and told his father that they could afford to put on the pageant themselves, and so Aras approved the costs.
June 15, 2013: Emin posts a picture of himself in Las Vegas wearing a Trump International shirt and a "You're Fired!" hat.
Later that day, Aras, Emin, and Trump formalize the deal to bring the Miss Universe pageant to Moscow. CNN reported on Wednesday that it had obtained video footage from the dinner.
Goldstone is seated next to Emin in the above photo, which the singer posted to his Instagram. Trump lawyer Michael Cohen appears to be seated next to Goldstone. Aras is sitting across from Trump, as is also apparent from the CNN report of the video footage from the dinner.
CNN also reported that Trump aide Keith Schiller was in attendance, as were Aras's wife, Irina, and Emin's sister, Sheyla.
Trump refers to the Agalarovs as "the most powerful people in Russia" while walking the red carpet.
“These are the most powerful people in all of Russia, the richest men in Russia,” he said in the footage obtained by CNN.
During the pageant, Trump announces that Miss Universe 2013 will be held in Moscow on Nov. 9 and introduces the Agalarovs.
On his Instagram account, Aras posts a video of the moment with the caption, "I'm happy to announce that Miss Universe 2013 will take place in Moscow at Crocus City Hall."
June 18, 2013: Trump tweets about Russian President Vladimir Putin.
By July 2013, Goldstone was off to Moscow, to work on preparations for the Miss Universe pageant.
Oct. 29, 2013: Aras is awarded the state Order of Honor by Russian President Vladimir Putin.
Nov. 8, 2013: Trump arrives in Moscow for the Miss Universe pageant.
In addition to the Miss Universe parties, Trump's arrival included another more private and elite event. As Trump later told Real Estate Weekly, "almost all of the oligarchs were in the room."
Bloomberg News reported that the event was hosted by Aras Agalarov and Herman Gref, the chief executive officer of state-controlled Sberbank PJSC, Russia’s biggest bank. The party was held at Nobu Moscow, an Agalarov property.
Nov. 9, 2013: In the morning, Trump films a cameo for Emin's next music video.
In the Forbes interview, Emin describes how he asked Trump to appear in the video.
“I said, ‘Mr. Trump, will you take part in my video?’ He said, ‘What do I have to do?’ I said, ‘You just have to fire me.’ He said, ‘How long is it going to take?’ I said, ‘Two takes, 15 minutes.’ He said, ‘Of course, I’ll do it,’ and he kindly agreed.”
Later, Trump, Aras, and Emin walk the red carpet for the pageant and hold a press conference.
Emin also performs during the Miss Universe pageant.
After the pageant, Trump is then given his own star.
Nov. 11, 2013: Trump tweets Aras a message of thanks for the "great weekend" he had with the Agalarov family.
Nov. 12, 2013: Trump tweets Emin about his "fantastic" performance during the Miss Universe pageant.
Nov. 20, 2013: Trump tweets Emin's "In Another Life" video, featuring himself.
Nov. 21, 2013: Emin tweets a behind-the-scenes clip of him and Trump talking during filming.
Feb. 4, 2014: Ivanka Trump poses for a photo with Emin at Crocus City in Moscow.
Feb. 19, 2014: Emin performs on the Today show during NBC's coverage of the Sochi Olympics.
Feb. 24, 2014: Rob Goldstone posts a picture of Trump filming something at Trump Tower in NYC.
March 8, 2014: Emin performs as an opening act at a high-profile concert at the Trump National Doral in Florida.
The concert was held during the 2014 World Golf Championships-Cadillac Championship, which the Trump property hosted. Emin opened for hip-hop artist Travie McCoy.
Following the performance, Emin posed for some photos with Trump.
And Ivanka Trump.
Although there are no photos of Emin with Donald Trump Jr. on his social media accounts, Getty photos place the eldest Trump son at the tournament on various days.
Aug. 24, 2014: Trump is featured in a profile of Emin on a Russian TV show called Young Millionaires.
Remember back in February when Goldstone posted a picture of Trump filming something? This was what he was filming.
In the clip, which is dubbed in Russian (and which BuzzFeed News has translated back to English), Trump says he has been talking with the Agalarovs about possibly constructing a huge building together and praises the family.
"He's in a family business with a very strong father, but he's also a wonderful person," Trump said. "I think Emin runs the family business well and his father likes what his son is doing. And I also think that he respects his son and lets him do what he loves.
"In business it's not important where you live, in America or Russia, the important thing is to understand each other."
December 2014: Trump records a glowing message for Emin's 35th birthday.
Emin, whose birthday is Dec. 12, will publish an excerpt from the video on Instagram two years later, following Trump's election.
May 20, 2015: Emin meets with Trump at his office in Trump Tower in NYC.
June 16, 2015: Trump announces he's running for president and Emin posts a message about Trump being his "friend."
In the Forbes interview, Emin said that his family company's plans to build a Trump Tower in Moscow with the Trump Organization were put on hold when the presidential run was announced.
"If he hadn’t run for president, we would probably be in the construction phase today, because he’s a great person, very trusted on our side and a great developer," he said.