The conflict known as the Ambush at Mon Calamari, alternatively referred to as the Attack on Mon Calamari, unfolded in 1 BBY. Early in the Galactic Civil War, Palpatine anticipated the Mon Calamari's potential alliance with the burgeoning Rebel Alliance. To forestall this, an organized raid was launched against the shipbuilding facilities.
Even though the Imperials had previously launched assaults on Mon Calamari, the Emperor remained convinced that the species would eventually align with the expanding rebellion. Moreover, the Mon Calamari were actively constructing additional capital ships. Should the Mon Calamari Orbital Shipyards throw their lot in with the Rebellion, the Alliance Fleet would gain the capacity to challenge Imperial Star Destroyers on a more even playing field.
Upon emerging from hyperspace, Imperial forces declared the planet to be under Imperial dominion. However, a substantial Rebel force, bolstered by a space station, launched an assault against the invading Imperial fleet. The Imperials then initiated maneuvers against the Rebel forces.
The Imperial Navy prioritized the space station, systematically destroying its hangar and numerous weapon emplacements. Despite enduring heavy fire from the remaining Rebel fleet, the Imperial Navy began to gain a decisive advantage.
At this point, two fully operational Mon Cal Star Cruisers entered the fray, flanking the Imperials. After completing the destruction of the space station, the Imperial fleet engaged the two capital ships. Despite suffering significant losses, Imperial reinforcements continued to arrive, ultimately leading to the destruction of the MC80 cruisers. The surviving Imperial vessels then eliminated the remaining enemy forces.
The Imperial fleet took many free Mon Calamari captive, intending to use them as a source of forced labor. Simultaneously, the fleet seized starship designs and relocated them to a base situated on Carida.
However, Imperial control over the planet proved to be temporary. The stolen plans were subsequently recovered, and a subsequent Imperial counteroffensive met with failure.
This specific engagement was featured as the fifth mission within the Imperial campaign of the 2006 video game Star Wars: Empire at War.