The MLRS (using the Guided Multiple Launch Rocket System (GMLRS) rockets) is not new being deployed in 1983 in the tracked M993 vehicle as part of the whole M270/270A1 MLRS system and first used in GW1.
In 2003 low-rate production of the M142 HIMARS (High Mobility Artillery Rocket System) began. It is limited to a single 6-round pod as opposed to the standard two for the M270 and its variants.
Currently in development is the extension of the range of the Guided Multiple Launch Rocket System (GMLRS) rockets to ~93 miles.