Following the inevitable career in karting, Christian switched to single-seaters in 1999 aged 16. Competing in the Formula BMW ADAC Junior Cup, he won his debut race and went on to take three more wins resulting in him finishing fourth in the championship.
In 2000 he moved up to the Formula BMW ADAC Championship, finishing tenth overall and third highest placed rookie. The following year he finished third in the championship courtesy of five convincing wins.
For 2002 Christian switched to Formula Renault competing in the German Championship and the Eurocup. Five wins and five pole positions meant the German Championship was in the bag, while the youngster finished fifth in the Eurocup and best rookie.
In 2003 the Austrian moved to the F3 Euro Series where four wins, seven poles, four fastest laps and nine visits to the podium resulted in the runner-up position, though the twenty-year-old was awarded 'rookie of the year' title.
Along the way Christian also found time to dominate the prestigious Marlboro Masters event at the legendary Zandvoort track.
Making his F1 test debut with Jaguar in late 2003, Christian impressed the Ford-owned team: 'Christian was in as much control of himself as he was the car,' said Jaguar Racing boss David Pitchforth. 'He was extremely calm, composed and didn't seem remotely fazed by his first ever experience with a Formula One car. His technical feedback was excellent and there is no doubt in our minds about the potential of this exciting new young talent. Our decision to employ him as a race driver was based on merit, potential and speed.'
The shortcomings of the R5, not to mention Jaguar's off-track problems, hardly allowed Christian to show his true potential, however if Ford hadn't pulled out of F1 it is unlikely that the Austrian youngster would have been retained.
Following Red Bull's purchase of the Jaguar Racing team, Christian was quickly signed up, as were David Coulthard and 2004 F3000 champion Vitantonio Liuzzi.
One can only hope that Red Bull's decision to 'share' the second seat between Klien and Liuzzi made sense to someone within the Austrian organization, because to the rest of us it made no sense. Although Christian drove the majority of the races (14), the uncertainly over the drive wasn't good for either him or his teammate.
That said, the Austrian delivered a number of fine performances, most notably his convincing fifth place in China. There were also a number of very impressive qualifying performances also - helped, of course, by David Coulthard's unease with the 'hot lap' format.
Having purchased Minardi and re-branded it Scuderia Toro Rosso, Red Bull now had two teams across which it could spread its driver load. Consequently, Christian was handed the second drive with the 'works' team.
Having qualified and finished eighth in Bahrain, the season couldn't have got off to a better start. However, as the season progressed the frustration set in, not helped by a number of technical failures and whispers of Robert Doornbos - managed by team boss Christian Horner - being drafted in.
Christian was under enormous pressure from Red Bull to commit to its Champ Car or DTM programme for 2007. However, his mind was firmly set on remaining in F1, consequently he turned down the offers, at which point, with three races remaining, Red Bull pulled the plug.
With Anthony Davidson off to Super Aguri, there was a (test) vacancy at Honda, however, Martin Brundle, who manages Coulthard, a close friend of Gil de Ferran, was working hard on getting the seat for Gary Paffett.
Whether it was the kind of money Paffet's management was looking for, or the sudden realization that in Christian it had a driver with almost 50 Grands Prix under his belt, we shall never know. However, the fact is that the Japanese team finally chose to sign the Austrian as support to Button and Barrichello.
In pre-season testing, Button described the RA107 as a "piece of shit", and he was correct. There was little that Button, the highly experienced Rubens Barrichello or Christian could do about it.
The new test rules meant that Christian got few outings in the car, and consequently, like Honda, he hoped that something better would come along for 2008.
At season end however, Honda opted to part company with the Austrian who was now eyeing a race seat with the new Force India team. Despite a couple of impressive tests however, the drive went to Giancarlo Fisichella, a deal thought to be more about money than outright talent.
Just as it looked as though Christian would have to seek employment outside F1, BMW snapped up the Austrian, team boss Mario Theissen admitting; "We wanted a third driver with Formula One racing experience". Despite the further reduction of testing in 2008, Christian was one of the busier test drivers, though towards the end of the season - much to Robert Kubica's frustration - this involved the 2009 car.
In addition to his F1 commitments with BMW, Christian contested the legendary Le Mans 24 Hours with Peugeot. Partnered by former F1 drivers Ricardo Zonta and Franck Montagny, the Austrian finished third, this in turn led to a drive in the Petit Le Mans with Peugeot's factory drivers Marc Gené and Nicolas Minassian, the trio finishing third at Road Atlanta.
Retained by BMW in 2009 the even stricter test rules meant there was even less F1 work for Christian to do. However, he was able to keep his motor sport CV up to date courtesy of a win at Spa in the 1,000kms sports car race with Peugeot and sixth place overall in the Le Mans 24-hours, not to mention fastest race lap.
While Bernie Ecclestone said the Austrian was a "good bet" to get a call from Sauber for 2010 it was not to be. Instead Christian eventually found himself as second test driver with Hispania, a team that didn't turn a wheel until the first practice session of the season… and even then only one car was complete.
Although nobody really expected to see Christian in the F100, in Singapore the Austrian was called upon to replace Sakon Yamamoto who was suffering from food poisoning - even though the Japanese driver was well enough to take part in promotional duties for the team.
Retiring after just 31 laps, most thought that was the last we'd see of the Austrian. However, the Spanish outfit subsequently put him its second car for the two final races of the season. Interestingly, in two of those three races he out-qualified his teammate Bruno Senna.
With precious little else on offer for 2011, Christian was hoping to continue with Hispania however, the Spanish team eventually settled on Tonio Liuzzi and Narain Karthikeyan, who returned to F1 after a five year absence.
Christian, having clearly given up on F1, is now racing in a number of different categories including endurance racing, sports cars and V8 Supercars. He was close to a deal with Peugeot to race in the World Endurance Championship in 2012 before the French company withdrew from racing. He has taken part in a number of V8 Supercar drives, including the Bathurst 1000 where he teamed up with Russell Ingall.