Johan de Nysschen has been given his marching orders after four years

Johan de Nysschen has been suddenly deposed as president of Cadillac, with his place being taken by Steve Carlisle with immediate effect.

Carlisle steps up from his previous role as head of GM Canada. Between 2010 and 2014 Carlisle was the head of global product planning, and prior to this he served as head of GM's south-east Asian operations and, briefly, head of sales in the US.

The South African-born de Nysschen started as head of Cadillac in September 2014 after stints as global head of Infiniti and US chief of Audi.

In a statement, Dan Ammann, president of GM said: "We appreciate Johan’s efforts over the last four years in setting a stronger foundation for Cadillac.

"Looking forward, the world is changing rapidly, and, beginning with the launch of the new XT4, it is paramount that we capitalise immediately on the opportunities that arise from this rate of change. This move will further accelerate our efforts in that regard.”

According to Automotive News, de Nysschen and the GM board fell out over the speed of Cadillac's product renewal, with the parent company wanting to make hay while the sun shone on the US market. De Nysschen, its said, was more conscious of brand's poor image, and preferred rebuilding the marque more slowly.

"I greatly admire and respect the GM top leadership but, in the end, I would conclude that in their opinion, I did not challenge hard enough," de Nysschen told the industry publication. "Accordingly, they exercised their prerogative to change leadership. It happens. It's not personal, it's business."

Top: Johan de Nysschen. Above: Steve Carlisle.

Upon his appointment in 2014, de Nysschen aggressively attempted to make Cadillac more independent from GM and its more mainstream brands. In his early days, he moved the brand's headquarters from Detroit to New York City.

Reminiscent of his time at the helm of Infiniti, de Nysschen also instituted a renaming of brand's models, with all of the crossovers to be given the XT prefix, and sedans, coupes and wagons to carry the CT prefix. All of these prefixes would be followed by a single digit denoting the car's position in the range.

Perhaps learning a lesson from Infiniti, where all its names (FX, M, Q, G, EX and JX) were streamlined almost overnight to just two prefixes (Q for regular cars and QX for crossovers), Cadillac's renaming game would only take place as new models were introduced.

Under de Nysschen's watch Cadillac has developed an engine to call its own for the first time in over a decade, with the company debuting a new 4.2-litre twin-turbo V8 in its CT6 V-Sport earlier this year.

The hand-built engine generates 410kW of power and 850Nm of torque, and gives the brand a weapon to use against BMW M, Mercedes-AMG and Audi RS.

Under Project Pinnacle, de Nysschen also sought to reform the dealer experience for Cadillac customers. While buyers and owners are now able to enjoy an experience more akin to that offered by Lexus and Audi, the project drew ire from the brand's dealers as they were forced to take on most of the financial risk for the upgraded amenities and services.

Above: Cadillac XT4.

Cadillac sales are up globally, thanks to improved interest from buyers in China, but the brand's sales have fallen consistently in the US.

As Bob Lutz points out in a thinkpiece for Road & Track, this is partially down to de Nysschen's winding back of incentives and overly generous lease plans.

It should also be noted, though, the brand has a range heavy with sedans in a market hungry for crossovers. It only recently launched the XT4 to complement the mid-size XT5 and the larger-than-life Escalade.