Steve Bannon is out as Donald Trump's White House adviser. White House Press Secretary Hope Hicks issued a statement that said Cheif of Staff John Kelly and Mr Bannon had “mutually agreed” that 18 August would be the former Breitbart executive's final day.

Here are 5 reasons his departure has likely been in the making since Mr Trump took office.

He had a strained relationship with son-in-law-in-Chief Jared Kushner

When Mr Bannon was appointed as chief strategist, former Klu Klux Klan leader David Duke told CNN Mr Trump's decision "excellent."

He also said Mr Bannon was "creating the ideological aspects of where we’re going" as a white supremacist movement. His former news organisation, Breitbart, also published several articles of people pushing an anti-Muslim agenda.

Mr Bannon has long been said to have prodded the President into not alienating white supremacists because they are an active part of the Trump base of support.

It goes beyond faith however. Mr Bannon ran what he referred to as the "platform for the alt-right" while Jared Kushner and wife Ivanka Trump are moderates who have contributed to Democratic candidates in the past.

Per the New York Times, Mr Bannon detested that fact and during a particular loud row he said to Mr Kushner: ""Here’s the reason there’s no middle ground: You’re a Democrat."

Mr Trump had said in the past to the New York Post: "Steve is a good guy, but I told them to straighten it out or I will."

Anthony Scaramucci's comments may have pointed to a personal agenda

Mr Bannon, as early as 2013, has said he is a "Leninist" and that his main goal was to "destroy all of today's establishment". Whether he actually came into the White House four years later with that agenda is unclear, but reports have suggested he did have a personal agenda - in addition to a personal publicist - and despised "establishment" Republicans like former Chief of Staff Reince Preibus who came from directly from the GOP.

Scaramucci to Colbert: 'If it were up to me, Bannon would be gone'

As Vanity Fair reported, each of the senior staffers has their own "brand" without a cohesive policy from an inconsistent President.

The short-lived Communications Director Anthony Scaramucci may have offered a glimpse into the behind-the-scenes agenda of Mr Bannon when he gave an expletive-laden interview to the New Yorker.

“I’m not Steve Bannon, I’m not trying to suck my own c**k...I’m not trying to build my own brand off the f**king strength of the President. I’m here to serve the country," Mr Scaramucci vented to a reporter and probing him for the source of yet another leak from White House.

Mr Bannon has reportedly been the source of leaks on stories critical of National Security Adviser HR McMaster as well.

Newscorp CEO and longtime Trump ally Rupert Murdoch said he had to go

Mr Scaramucci was not the only one Mr Bannon had rubbed the wrong way. Mr Murdoch has known Mr Trump since the 1980s when the Australian CEO's New York Post regularly featured the young real estate magnate's exploits in its tabloid pages.

Mr Murdoch has "repeatedly urged" Mr Trump to fire Mr Bannon according to the New York Times. Given the President's regular viewing of Mr Murdoch's Fox News channel for positive reinforcement and a gauge of his base, the close relationship is one on which he depends.

Understanding the television base, Mr Murdoch may have encouraged the President to fall more into the "mainstream" of Republicans as Mr Scaramucci had said he wanted before his exit.

He may have been seen as stealing the spotlight from Mr Trump

The President once said Mr Bannon was a "decent guy" who "gets a bad rap" but that appears to have changed in recent months.

A senior official told Vanity Fair that Mr Bannon is "is very talented at making himself seem the hero of the conservatives who elected" the President.

The perception that he is responsible for the President's popularity is said to have "annoyed" Mr Trump after the strategist appeared on the cover of Time magazine with the words "the great manipulator" and in the magazine's story asking if he was "the second most powerful man" in the country.

Around the time of the magazine cover, Mr Bannon was removed from his brief tenure on the National Security Council, an appointment that was reportedly made without Mr Trump's knowledge early in his presidency.

Just ahead of Mr Bannon's exit, Mr Trump's favourability rating was at a historic low.

Mr Bannon set the stage for these tensions years ago

Despite the tensions in the West Wing, Mr Bannon had set the stage for his departure from the White House for years.

For years, Mr Bannon - through the Breitbart outlet and otherwise - has pushed for what many have characterised as an anti-Islam and misogynist message, playing host to controversial and polarising characters like Pamela Gellar and Milo Yiannopoulos.

Between being a "Leninist" that wants to "bring everything crashing down" and having a daughter who graduated from West Point and served in Iraq who he is "very proud of," Mr Bannon appears to be a unique character not seen in the larger Republican party.