The XR designation was first used in 1966 on a performance version of the Australian Ford Falcon XR. This car was sold alongside the American made Ford Mustang. XR stood for eXport Right-hand drive. This designation was so popular it was used a year later on the Mercury Cougar XR-7.

The Ford Sierra was derived from the German Ford Taunus and the British Ford Cortina. The first one , known as The Mk. 1 Ford Cortina, was initially introduced in 1962. In 1963 Ford came up with a performance version of this car. It was equipped with a Lotus 4 cylinder double overhead cam engine, and was therefore named Lotus Cortina. This car was thus an early ancestor of the XR Sierras. In 1967 a new generation Ford Cortina (the Mk. 2) was introduced, and the following year later a Lotus Cortina version of this car was made available.

Meanwhile, in Germany performance versions of their Fords were also introduced. These were given the designation RS, which was presumably derived from Rallye Sport. Thus the front wheel driven V4 powered 15M, as well as the rear wheel driven V6 powered 26M were available in RS versions.

By the end of the 1960's Ford of Europe decided to replace their British and German cars with common models, thereby eliminating in-house competition. Therefore in 1970 the rear wheel driven inline four powered Cortina and the front wheel driven V4 powered 12M and 15M were replaced by a common model. This was equipped with an inline four and was rear wheel driven. For the German cars the name Taunus was re-introduced, while the British cars retained the name Cortina. The latter were called Cortina Mk. 3. Differences in these cars could be found in their rooflines, their tailgates and their grills. The Taunus had a mini Thunderbird grill, while that of the Cortina was flatter.

In 1976 these were replaced by new models which retained the names Taunus and Cortina, but were otherwise virtually identical. The British car was thus known as the Cortina Mk. 4. That year 2.0 and 2.3 litre V6 engines were offered as an option on the Taunus, and a year later the Cortina got the Cologne 2.3 litre option. These were the first of the Sierra's predecessors to be equipped with a six-cylinder engine as a factory option, thereby foreshadowing the Sierra XR4i and 4X4. However, this was not the first V6 Cortina which was made available to the public. In the late 1960's the company Race Proved developed and offered, with Ford's assistance, a truly fierce version of the Cortina GT and 1600E, called the Savage, in which the 3.0 litre Essex V6 engine from the Zephyr/Zodiac, together with its gearbox, was neatly shoehorned into the bodyshell of the Mark 2 Cortina.

In 1979 the Taunus/Cortina was given a thorough updating, which was more than a facelift but less than a new model. It was officially known as the Taunus/Cortina 80, but the British version eventually became known as the Cortina Mark 5.

In Australia the later Cortinas (Mark III and onwards) were since 1972 available with the straight six engines out of the Falcons. These had a displacement of 200 cu. in. (3.3 litres) and 250 cu. in. (4.1 litres). According to Adrian Ryan of Ford-Australia: "... The six wasn't the greatest success story for Ford Australia. The cars didn't handle all that well due to the extra weight up front. They did accelerate like a racing car, though!".

In 1982 the Taunus/Cortina was replaced by the Sierra. Its style was a radical break from the past, as Fords had previously retained a very traditional angular style. Its name was presumably introduced as Taunus was difficult for some to pronounce.

The XRs were not the only performance Fords to use the Sierra body, as Ford made Cosworth versions of this car. XR denoted "warm" versions of the respective cars (Fiestas, Escorts and Sierras), while RS denoted the "hot" versions of these cars.

In the following each car concerned by this Website will be described. The cars are sorted in chronological order and by continent.