The legend of the creation of these island say that during a very ancient time ninety-nine ghosts angered the heavens by nearly destroying the world causing the heavens to strike them down. Their corpse drifted down the Thousand Carp River and reached the Static Stream Estuary before sinking into the ocean creating the ninety-nine islands. While their bodies became the islands, their hair turned into the Ghost Locust Trees.
During Li Qiye's destruction of the Ancestral Domain he activated the Ghost's Origin Ancestral Key revealing that the islands were in fact gigantic cannons called Primal Ghost-Cannons. While the hundredth Lost mythical island was the prison of the Ghost-Devourer.