Kaer existed as a gas giant located within the Siskeen system of the Hunnoverrs sector.
At the commencement of the Clone Wars, the InterGalactic Banking Clan erected the Kaer Orbital Platform. Throughout the Clone Wars period, the Confederacy of Independent Systems utilized this base as a manufacturing hub for additional droid troops and various vehicles.
A tibanna gas mining platform, known as Kaer Station, was built within its atmosphere; however, the Black Sun crime syndicate later seized control, transforming it into a stronghold for Vigo Lun Rask in 137 ABY.
The initial reference to Kaer appeared in the databank of the game titled Star Wars: Galactic Battlegrounds: Clone Campaigns. In Legacy (2006) 37, the Siskeen system's Kaer was incorrectly situated within the Arkanis sector.
Lily Mansfield designed the level in Clone Campaigns and selected the name Kaer, drawing inspiration from caer, the Welsh term for fortress.