A battle took place shortly before the Battle of Yavin on the planet Kalaan.
The Rebel Alliance had established a base on the world, taking up refuge among the Kalaanites in Kalaan City. Learning of Kalaan's connection to the Rebellion, Imperial commanders planned to subjugate the planet and root out any Rebel presence. A task force of five Imperial-class Star Destroyers arrived in orbit above the planet deployed a cloud of dropships, mostly Sentinel-class landing crafts and Theta-class AT-AT barges. Emerging from the drop ships was a combined force of AT-AT, AT-AA, AT-ST and AT-PT walkers, with 74-Z speeder bikes providing combat support.
Rebel hovertanks engage Imperial walkers.
The columns of Imperial armor closed on the city. Some distance out, they were met by skirmish line of T1-B hovertanks. The hovertanks proved no match for the AT-STs and AT-ATs until the heavier T3-B heavy attack tanks rolled over a ridge to support them. Combined with air support from T-47 airspeeders and Y-wing starfighters, the Rebels were able to put a dent in the Imperial columns.
Despite the temporary halting of the Imperial force, the Rebels' efforts were to no avail, and the city fell to the Empire. Squadrons of TIE/sa bombers demolished the city, leaving mostly rubble.
In the aftermath of the battle, stormtrooper squads combed the ruins of the city. On one such patrol, a unit of Cattena Squadron had its sergeant killed, at which point Corporal Brenn Tantor took command. Captain Beri Tulon, scouting the battlefield for talented commanders to put to use in the BHCI program, took notice of Tantor's performance.
Tulon met Tantor's squad in time to see Brenn tending to his brother Dellis, who had been shot by a Kalaanite. Tulon promoted Brenn to lieutenant and pulled him for the project. Dellis came along to receive medical attention.
As a result of the battle, the Empire took control of the planet, built a prison, and stripped much of it of vegetation, feeding the resentments of the Kalaanite resistance.
- The Essential Atlas