[3] The X2 project began in 1969 as a collaboration between Kalmar Verkstad, Swedish State Railways (SJ), and ASEA.

ABB was responsible for manufacturing the electrical components, while Kalmar Verkstad handled the mechanical design and construction.

[5] The X2 was developed to address the challenges posed by Sweden's railway network, which features numerous sharp curves due to the country's geography.

[6] At the same time, Sweden’s low population density made the construction of dedicated high-speed rail lines impractical before 1990.

To overcome these constraints, the X2 was designed as a tilting train, allowing it to maintain higher speeds while navigating curves.

[8] In the late 1960s, an X1 multiple unit was modified with a tilting carbody on new Asea bogies with pneumatic control.

Manufacturing introduced new welding and structural techniques, producing a rigid, collision-absorbing body with reduced corrosion and maintenance needs.

The maximum speed allowed in regular traffic is 200 km/h (125 mph) for safety reasons – the signalling system (and systems like the catenary) are not built for higher speeds, and it shares the track with regular trains (like in most countries); also, most of the lines it uses were built in the mid-to-late 19th century.

The 19th century railways Stockholm–Gothenburg/Malmö are relatively straight, since they were planned the shortest way without taking intermediate cities into account, and the landscape is relatively flat.

The fastest part is Katrineholm–Skövde, a distance of 180 km (110 mi) that is covered in 1 hour and 2 minutes, resulting in an average speed of 174.2 km/h (108 mph).

In its original appearance, the X 2000's carriages, constructed from stainless steel, were partially painted with blue and dark grey stripes.

During this update, electrical outlets were added to each seat, the upholstery was replaced, and the trains were equipped with Wi-Fi.

[21]In January 2014, SJ announced that it was to invest 3.5 billion SEK in the modernisation and repowering of its X 2000 fleet, in order to extend the life of the trains by 20–25 years.

It also proved to Swedes that rail is a viable solution not just in exotic densely populated foreign countries, but also at home in Sweden.

In 1991, the Swedish government started a massive investment program, spending 5–10 billion kronor annually on improvements to the rail network.

A milestone was reached in the late 1990s when the number of trips taken by train in Sweden exceeded the 1940s level for the first time.

It was used in revenue service on the Northeast Corridor between New Haven, CT and Washington DC, via New York City, for about five months, from February until May and from August until September 1993.

After conducting a statewide tour of New South Wales in March 1995, they were used on Sydney to Canberra services from April to June 1995.

There were competitors which had lower prices, including Pendolino and ICE T. The Guangshen Railway Company in China leased and later purchased outright an X 2000 train which it named Xinshisu (New Speed).

The cab car (110986 CUB2XFK) has been cosmetically restored and repainted, losing its Chinese livery, and will be displayed at the Swedish Railway Museum when it reopens.

The power car (2088 CX2) is currently used as a testbed for the ongoing refurbishment program, and the five intermediate trailers were repaired and re-entered service in 2020.