The Red Bull F1 exit that led to Christian Horner's demise wasn't Adrian Newey

Christian Horner's Red Bull empire has fallen after 20 years. In the end, it seems it was a combination of performance and politics that led to the downfall of a man who, 18 months ago, survived a scandal that would have taken most others down.

Did the accusation of inappropriate behaviour towards a female colleague in the Formula 1 team, made last February, of which he was cleared by an independent KC hired by Red Bull to investigate the claim, have any bearing on his exit? Possibly, though nothing new has happened on that topic of late.

But it was certainly the catalyst for those who wanted Horner gone to make their move. People like star driver Max Verstappen's father Jos, who responded to that controversy by calling for the Brit's head in public and has spent the last 18 months trying to undermine him at every opportunity.

Long-serving Red Bull adviser Helmut Marko was also a thorn in Horner's side at times, while the central Red Bull leadership in Austria also had their doubts. Mark Mateschitz, who inherited 49 percent of Red Bull GmbH when his father and company founder Dietrich died in October 2022, was not as much of a fan of Horner as his old man was.

Sign up to our free weekly F1 newsletter, Pit Lane Chronicle, by entering your email address below so that every new edition lands straight in your inbox!

Nor was Oliver Mintzlaff, who in 2022 was installed as chief executive of corporate projects and new investments – in charge of the company's sporting efforts which effectively made him Horner's boss. He was believed to have been unhappy with how much power the Brit wielded in his duel role as both team principal and chief executive of Red Bull Racing.

But Horner had some crucial protection, in the form of Thai businessman Chalerm Yoovidhya. The 49 percent of Red Bull owned by his family, as well as his own personal two percent stake, meant he had majority control and, despite the best efforts of the Austrian leadership, he stood firm and refused to replace Horner.

READ MORE: Christian Horner Red Bull F1 exit comes after three key things changed

READ MORE: Christian Horner successor makes feelings about axed Red Bull F1 boss very clear

That, of course, has since changed. Horner's exit, announced on Wednesday but communicated to the long-serving leader of the F1 team a day earlier, comes amid concerns that star driver Max Verstappen could quit for rivals Mercedes, and a performance drop-off from the team which has seen them fall out of contention for both titles.

Many people have pointed to the departure of Adrian Newey as the starting point for that decline. The Brit is one of the most celebrated designers in F1 history and his departure after 18 years last season, before he agreed to join Aston Martin, coincided with the beginning of their drop in performance.

Losing his expertise would certainly have been a blow, though there were upsides. As much as Newey was frustrated that others within the team were taking credit for his work, his presence also created a discontent as other leading designers felt they actually weren't getting enough credit – because Newey received all the plaudits, particularly from outside the team. Sources indicate that Verstappen was also frustrated with Newey towards the end.

And then there was the departure of Jonathan Wheatley, who joined in 2006 as team manager and later became sporting director, with an unrivalled knowledge of the regulations and strong command of Red Bull's pit crew who became the best in the business under his leadership.

But he wanted to make the next step in his career and become team principal. With Horner seemingly there for the long haul, he decided last summer that his future laid elsewhere and accepted an approach from Audi to spearhead their new F1 project.

But multiple sources inside Red Bull Racing have indicated that the departure actually felt the most internally was that of Rob Marshall. He was another who joined the fledgling outfit in 2006 as chief designer and went on to become their head of engineering, but left in early 2023 before starting work at McLaren in January the following year.

In the time since, Red Bull have been knocked off their perch and McLaren have succeeded them as the team with by far the most competitive car on the grid. Chiefs at the F1 team, including Horner before his exit, felt that Marshall's defection was a key factor in that shift and that his absence has been far more detrimental to their performance than any other.

Many people will point to the scandal last season as the beginning of the end of Horner's long tenure as commander-in-chief at Red Bull Racing. But it seems Marshall's exit a year earlier was the true catalyst for the performance decline which turned out to be the straw that broke the camel's back.