The Battle of the Lannik system occurred during the Jedi Civil War, a war fought between the Galactic Republic and the Sith Empire led by Darth Revan. After the Republic's victory on Rodia, they initiated a military campaign against the Sith Empire. From Rodia, the Republic forces defeated the Sith on Mon Gazza and then progressed through systems including Ando, Manda, and Bothawui, ultimately arriving at Lannik. The Republic then achieved victory against the Sith Empire in a confrontation there.
The Essential Atlas is the only place where the Battle of Lannik is depicted. The precise date of the battle is not specified; instead, it is visually represented on the galactic map, rather than described in detail. This battle is portrayed as a component of a Republic offensive that originated at Rodia and culminated at Lannik.