The AS90 is a British self-propelled artillery system. In the 1970s, the United Kingdom, Germany, and Italy began searching for replacements for their armies' outdated self-propelled howitzers. To this end, the countries launched the joint SP70 project. However, the project encountered difficulties, so British engineers decided to work on their own artillery system in parallel. Development of the new self-propelled artillery system began in 1982. During this period, conceptual studies of a modern artillery chassis were initiated, building on work from the GBT-155 artillery system.

As part of the program, other companies submitted designs for the general tender. After a rapid evaluation and testing phase, Vickers Shipbuilding and Engineering's design was selected. In March 1985, the final winner was determined, and the new system was designated AS90 (short for Artillery System for the 1990s). This artillery system ultimately entered service with five field artillery regiments, replacing the British Army's 105 mm FV433 Abbot self-propelled howitzers and American 155 mm M109 systems. The British Army first deployed the AS90 in Bosnia and Kosovo in the 1990s as part of NATO missions. It was also used in the Iraq War in 2003.

The AS90 was introduced in Update 2.55 "Ninth Wave". Like many NATO self-propelled howitzers, the AS90 is equipped with a 155mm gun with a fast reload rate and a typical late SPH ammunition set, including normal HE shells for ground targets and HE shells with proximity fuzes for aircraft. However, the price for such powerful armament is relatively weak protection and a large size. Any direct hit to the turret or hull can result in the AS90's destruction.