The 53-year-old New Yorker -- whose profanity-laden rant against colleagues gained him global notoriety -- was fired as four-star general John Kelly began his quest to impose order on an administration careening out of control.
During its first six months in office, Trump's White House has been beset by scandal, investigations, infighting, leaks, sackings, resignations, stinging legislative defeats and historically low approval ratings.
Scaramucci was brought in a little over a week ago to get the White House back on message, but quickly prompted negative headlines of his own.
He publicly called then colleague and chief of staff Reince Priebus -- who was forced out last week -- a "paranoid schizophrenic" and denounced chief White House strategist Steve Bannon in lurid sexual terms.
The White House refused to say whether it was Trump or Kelly who precipitated Scaramucci's shock departure, but it seems clear that both were unhappy with his presence.
"The president firmly felt that Anthony's comments were inappropriate for a person in that position," said White House spokeswoman Sarah Huckabee Sanders.
Sanders added that everyone in the West Wing -- including Scaramucci -- reported to Kelly, a return to tradition for a White House that has been anything but.
"General Kelly has the full authority to operate within the White House, and all staff will report to him," said Sanders. "That includes everybody at the White House."
Kelly inherits the day-to-day running of an administration that -- far from marching in lockstep -- looks like a regiment pinned down by heavy fire, getting conflicting orders from their commander and squabbling over the way forward.
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In previous administrations, the chief of staff has acted as a chief operating officer: organizing staff, managing the president's schedule and deciding who gets access to him when.
In Trump's White House, a rotating cast of family and staff with unclear roles and opaque job titles seemed to be able to walk into the Oval Office at will or get the president's ear.
Despite Kelly's apparent empowerment, many question whether anyone can rein in the mercurial, Twitter-happy Trump, who has appeared to encourage the infighting among various factions vying for influence in his administration.
All the president's generals
After an Oval Office swearing-in ceremony before the afternoon theatrics, Trump confidently predicted Kelly, a 67-year-old combat veteran, would do a "spectacular job."
"I predict that General Kelly will go down as, in terms of the position of chief of staff, one of the great(est) ever," Trump said.
"What he has done in terms of homeland security is record-shattering, if you look at the border, if you look at the tremendous results we've had."
Kelly replaces Priebus, a Republican Party operative who was ousted last week after the spectacular failure of Trump's bid to repeal Obamacare and as his ugly feud with Scaramucci spilled into the open.
It was not immediately clear who would replace Scaramucci.
Former spokesman Sean Spicer, who resigned a little over a week ago, refused to comment on whether he will now remain in the White House beyond his planned August departure.
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No chaos
Earlier in the day, Trump -- ever determined to project success -- insisted Monday that there was no "chaos" at the White House, which he said was running as a finely tuned machine.
"I think we're doing incredibly well. The economy is doing incredibly well, and many other things. So we're starting from a really good base," he told a cabinet meeting.
But aside from the economy, there has been little reason for Trump to cheer.
Under pressure from a widening probe into his campaign's contacts with Russia last year, Trump last week publicly shamed his own attorney general Jeff Sessions for disloyalty, alarming his conservative base, before turning on Priebus.
In another tweet Monday, Trump hinted that Congress's own health insurance plan should be replaced for its failure to repeal Obamacare, his predecessor's signature reform of the US health care system.
"If Obamacare is hurting people & it is, why shouldn't it hurt the insurance companies and why should Congress not be paying what public pays?" he wrote.
The billionaire Republican has parted ways with a number of top officials beyond Priebus and Scaramucci, including his national security advisor, deputy national security advisor and FBI director, among others -- an unparalleled turnover for such a young presidency.
On the global stage, Trump faces the stark challenge of a North Korea that could be on the verge of marrying nuclear and ballistic missile technology.
"We'll handle North Korea. We're going to be able to handle them. It will be handled. We handle everything. Thank you very much," Trump said.
