The Cygnus B system, also known as the Cygnus system, existed within the Esaga sector, which was situated in the Slice region of the Mid Rim. This star system shared its designation with Cygnus Spaceworks, a starship manufacturing enterprise. This company's base of operations was within the Cygnus Star Empire, a small group of planets found along the Oktos Route hyperlane in the Mid Rim. Doctor Milanda Vorgan, a xenolinguist, theorized that these planets were surrendered by Hutt Clan-General Kossak Inijic Ar'durv as a form of appeasement to the allies of Xim the Despot, a foe of the Hutt Empire, during the Xim Wars. This conflict between Xim and the Hutts occurred twenty-five millennia before the Battle of Yavin.
The Cygnus B system was the homeworld of giant algae-beds—immobile, sentient species classified as a super-brain. By 0 BBY, Luke Skywalker, a young man originating from Tatooine in the Outer Rim Territories, had encountered images depicting the giant algae-beds of the Cygnus B system.
John Chesterman conceived the Cygnus B system for "Cantina Communications," a short narrative featured in the sixteenth issue of Star Wars Official Poster Monthly magazine, released in 1979 by Paradise Press. The Essential Atlas, a reference book published in 2009, provided an abbreviated designation for the system and located it within grid square R-11.