It wasn’t even 8 a.m. on a Sunday morning, but Arthur Schwartz was ready to wage war.

The well-connected Republican strategist believed that President Trump’s former chief of staff, Reince Priebus, was running a negative publicity campaign against Anthony Scaramucci, the White House communications director who had been hired and promptly fired in just over a week.

Schwartz was an ally of Scaramucci, and wanted to hit back hard. So in a series of tweets, he claimed that Priebus, married with two children, was having an affair.

“Hey @Reince. Remember when people told you that it was me that was trashing you in the press? They were right. Happy to start again,” Schwartz threatened in one now-deleted tweet from July 2017.

“Hey @Reince45. Oops; @Reince – you’re unemployed now. Keep pushing this crap & I’ll star dropping oppo on you. Mistress much?” he wrote in another tweet that has since been removed.

The act of aggression backfired immediately, and an embarrassed Schwartz apologized to Priebus, telling the New York Daily News the allegations were “just rumors that have been going around for a while.”

The episode was a watershed moment for official Washington’s understanding of Schwartz. A longtime New York PR consultant, Schwartz had operated largely in the background of Republican politics for years. But now two of Schwartz’s longtime friends, Scaramucci and Steve Bannon, were at the center of power and attention in the new administration.

And whenever Schwartz believed his allies were being treated unfairly in the press, he went on offense against his perceived enemies.

In the nearly two years since he arrived in Washington with a new wave of Trump appointees, mid-level players, and hangers-on, Schwartz has gained a reputation as a fixer, behind-the-scenes operative, and social-media agitator with a particular specialty: shopping information on enemies and doing battle with reporters.

That’s helped him forge close relationships with numerous Trumpworld officials and family members like Donald Trump Jr. The two are now so close they spent last year’s Super Bowl together. Schwartz has served as a gatekeeper for many journalists looking to get in touch with the president’s son, and has occasionally served as his bulldog when negative stories are written about him.

“I don’t work in government, I don’t work for a campaign. I’m basically a fucking troll on Twitter,” Schwartz told The Daily Beast. But virtually every reporter in Washington covering Trumpworld, including Daily Beast reporters, has had contact with Schwartz, trading tidbits and enduring the occasional harangues.

Since November, The Daily Beast has interviewed close to two dozen people who have worked or interacted with him in the past five years in New York and Washington. Most asked to remain anonymous, some out of fear that Schwartz would attempt to retaliate.

"When he thinks you can be useful to him and push a narrative that advances his agenda, he will be your best friend,” said one reporter who has tussled with him. “But report something he doesn’t like and he will morph into what can only be described as an online terrorist.”

In the weeks before this story was published, nearly a dozen well-connected figures in Trumpworld, including current and former administration officials and members of Congress, called The Daily Beast to heap praise on Schwartz.

Several of Schwartz’s friends and associates told the The Daily Beast they value his loyalty, his lack of interest in using political connections for business favors, and his willingness to go to the mat for a friend in need of public defense.

“In high school, you’d have that one guy in your group who if you’re out at a party and somebody starts messing with anybody in your group, that guy would [stand up to] anyone there,” a former White House official close to Schwartz told The Daily Beast. “Arthur is the political equivalent of that.”

One example of his pugilistic approach came in June 2017. According to two sources familiar with what happened, Schwartz encouraged multiple reporters to write about an incident in which he claimed Politico Playbook writer Anna Palmer had gotten into a drunken argument over politics with several Trump-friendly journalists and allies in the Four Seasons hotel in Georgetown. Politico strongly disputed The Daily Caller’s reporting of the events at the time.

Betsy Rothstein, a longtime media and gossip reporter at The Daily Caller, ended up running the story, which mentioned that Schwartz was a witness to the events. Schwartz denied having pitched the story, but did say he “definitely got calls” from reporters about it. Rothstein did not respond to The Daily Beast's request for comment.

But if Schwartz was pleased about Rothstein's writeup of the Palmer incident, their relationship didn't last. Schwartz and Rothstein got into an argument after she posted a series of since-deleted vague tweets in which she said Schwartz helped her on stories occasionally.

Schwartz was furious and threatened to sue Rothstein, telling higher-ups at The Daily Caller that Rothstein exposed him as a secret source in a series of tweets.

“Betsy Rothstein put up a tweet saying I was one of her sources,” Schwartz said. “I told them, ‘You better get that down because I’ve never spoken to her on the record or I’m going to sue you.’”

Schwartz, 46, initially caught reporters’ interest by shopping tantalizing, amusing, and sometimes strange, nuggets of information.

Multiple people with direct knowledge told The Daily Beast that Schwartz has tried to shop stories to reporters about former Trump chief of staff John Kelly—who often butted heads with Trump loyalists—including a claim that he did not wash his hands after using the White House bathroom. Schwartz denied circulating the story and claimed he first heard the anecdote from a Daily Beast reporter. (Last week, however, Schwartz taunted Kelly, tweeting at him: “Don’t worry, General Jackass. Your time in the barrel is coming soon.”)

Schwartz was prone to sprinkling conversations with hints about his proximity to power within Trump world, and multiple reporters told The Daily Beast that he would show them bits of message exchanges between himself and people like Trump Jr. or Bannon. Schwartz denied that he had ever shown private messages to any reporters unless authorized to do so.

In some instances, Schwartz’s anger manifests itself very publicly, whether on his 45,000-follower Twitter feed—he insults CNN’s outspoken White House reporter Jim Acosta constantly—or in person. Numerous members of the media told The Daily Beast they have received angry late-night emails, strongly worded messages, or screaming phone calls from Schwartz.

Several years ago, Schwartz got into a heated expletive-laced public altercation with a CNBC producer at a bar in Manhattan, according to one source with direct knowledge of the incident. Asked about the confrontation, Schwartz first told The Daily Beast he did not recall the encounter, then denied it ever happened.

Last year, journalist Julia Ioffe was in the process of reporting out a long, detailed profile of Donald Trump Jr. for GQ. Schwartz, who had become an unofficial representative for the president’s son, was not pleased when a fact-checker from the magazine reached out to ask if Trump Jr. had ever experienced “Oedipal impulses.”

He blamed Ioffe, screaming threats about the various ways he’d ruin her life. And in the months after the story was published, Schwartz reportedly tried to make good on the threat.

As it happened, according to GQ, the fact-checker had misinterpreted a point in Ioffe’s draft, which never even mentioned “Oedipal impulses.” After the GQ story was published, Breitbart News obtained a copy of the fact-checking questions and successfully got GQ to part ways with the fact-checker. Schwartz confirmed that he warned Ioffe he would get a story about the fact-checker’s questions placed on Breitbart.

Schwartz’s allies argue that his aggressive style and unrelenting criticism of Washington journalists has been effective at intimidating reporters and influencing coverage of his close friends in Trumpworld. People close to him credit Schwartz with an uncanny ability to publicly make noise about perceived media biases and privately lobby popular right-wing commentators with large online followings to push out his chosen narratives.

“Arthur has been a good friend, and not only a supportive friend, but he's talented at his forte, and very skilled, and I've enjoyed knowing him,” said former Trump adviser Sam Nunberg, who said he’d met Schwartz socially in 2013. “He's highly skilled and efficient in communications, opposition research and advocacy. And he is ahead of the curve.”

Charlie Kirk, president of the right-wing student group Turning Points USA, said he couldn’t speak to Schwartz’s PR tactics, but praised the help he had provided to the organization without expecting favors in return.

Kirk, who said he got to know Schwartz at the opening of the American embassy in Jerusalem, called him a “generous donor” to TPUSA who had been extremely helpful in helping recruit other potential donors.

“Arthur’s become a really good friend,” he said. “He’s been phenomenal to me… He never asks anything out of me. I’m blown away by the amount he steps up to the plate.”

Schwartz came to be part of the pro-Trump orbit after floating for years through various Republican political circles.

The alumni magazine at Cardozo Law School (which Schwartz attended) and a 2004 book said Schwartz was a low-level legal associate who wrote under the pen name “Cornholio Esquire” on an early legal industry message board. Schwartz denied that this was his pen name, but confirmed he was an investor in the message board company.

Schwartz decided he was unhappy working at New York law firms, and found himself more at home in the public relations industry. He earned a reputation among flacks and reporters for his right-leaning beliefs, getting kudos from conservatives for publicly resigning from his job at comms firm MWW when it hired former Democratic Rep. Anthony Weiner.

He forged a bond with right-wing conservative Jewish activists including Zionist Organization of America president Mort Klein. One Schwartz client, former AIG chairman Hank Greenberg, helped him foster a closer connection to Republican power brokers, particularly those in New York politics.

Though he ran in New York Republican circles for years, Schwartz jumped on the Trump bandwagon late. A regular donor to Republican political candidates and causes, in 2015, he donated $2,700 to the presidential campaigns of former governors Jeb Bush and Chris Christie, according to Federal Election Commission documents.

But as Trump consolidated power within the GOP, Schwartz established close ties with high-profile Trump allies, ingratiating himself within the president’s inner circle as an informal outside adviser and loyal foot soldier.

Sources with direct knowledge said that at the beginning of the administration, Schwartz was “crucial” in successfully planting information that some officials in the White House wanted to give to trusted reporters. According to one source familiar with the incident, Schwartz last year advised junior White House staffer Andrew Giuliani to connect with Axios for a story about how Kelly refused to promote Giuliani despite Trump’s directive.

Bannon took Schwartz under his wing during the first months of the Trump administration. The two had known each other for years in conservative circles and were often spotted together during Bannon’s tenure as a top White House strategist. At times, various publications cited Schwartz as a Bannon spokesperson, adviser, and crisis responder. (Though Schwartz never served as an official spokesperson, Bannon did occasionally ask Schwartz to talk to reporters with whom he had a relationship.)

Richard Grenell, Trump’s ambassador to Germany, also found Schwartz to be an important ally. Three sources told The Daily Beast that when Senate Majority Leader Mitch McConnell considered putting Grenell’s nomination on hold, Schwartz contacted lawmakers’ offices on his behalf, pushed reporters to cover the story, and fired up grassroots conservatives to put pressure on conservative lawmakers.

Earlier this month, Schwartz acted as the ambassador’s attack dog, picking a fight with New York Times columnist Bret Stephens for using the innocuous phrase “Let me get this straight” while debating Grenell. “Get this ‘straight?’ Are you taking a shot at Ric because he’s gay? You’re a despicable human being,” he tweeted earlier this month.

Schwartz is often aggressive when he feels he or his pals are being personally besieged.

Two sources with knowledge said that in February 2018 he sent emails to several female journalists, demanding they defend him from Twitter attacks by liberal writer Molly Jong Fast.

“Respond to this tweet or lose my number,” he commanded. “Seriously.”

Schwartz initially said he didn’t recall such an email but when read a portion of it, he then confirmed he had sent it.

When Schwartz was asked for comment for this story, which has been in the works for two months, he launched into a tirade, falsely claiming The Daily Beast was engaged in a conspiracy with CNN to bring him down.

“I annoy some people at CNN, I got some people at CNN fired, and now it’s your job to look out for CNN,” he said.

He was referring to an incident in 2017, when CNN published a story claiming the Senate Intelligence Committee was investigating Scaramucci’s ties to a Russian investment fund.

A number of White House staffers and Trump allies happened to be at The Hay-Adams hotel when that story went online, according to one source who was present. Quickly, they set up shop in Schwartz’s room, as he suggested responses and pushed back on the story to reporters. The outside pressure campaign helped sow doubt at CNN about the story’s veracity and resulted in the ouster of multiple reporters.

Schwartz’s day job isn’t expressly political; he has worked as a consultant for clients with business concerning the Committee on Foreign Investment in the United States, which regulates foreign acquisitions of U.S. companies that may have national security repercussions.

But he finds plenty of time to go after his chosen targets in the media. In October, Schwartz shared homophobic tweets CNN White House reporter Kaitlan Collins posted years ago when she was in college. The Log Cabin Republicans, which represents gay conservatives, amplified the tweets, and Collins publicly apologized.

Schwartz told The Daily Beast he wasn’t sure if he was the first person to publicize the old tweets. He said someone flagged them for him and he thought they were “interesting,” so he tweeted them.

Schwartz has boasted of knowing of opposition-research packets on dozens of CNN reporters. CNN’s PR team has traded barbs with him on Twitter, and in 2016, BuzzFeed considered sending a letter to him after he continued to post on Twitter the bogus claim that former reporter Andrew Kaczynski misstated his congressional work history.

Schwartz told The Daily Beast that if he had issues with this story, he could take advantage of his relationship with Fox News host Tucker Carlson to respond.

“I’m gonna do eight minutes on Tucker about how you guys are basically CNN’s hit-piece bitches,” he vowed. Two sources at Fox News said they were unaware of any upcoming segments about The Daily Beast.