Deist is an island far to the north of Palamecia in Final Fantasy II. It is the homeland to Wyverns and Dragoons. It is Ricard Highwind's birthplace, and the Dragoon stronghold, Castle Deist, and Deist Cavern are located here as well.
Deist is known as the Kingdom of Dragoons. According to the Mysidia Library, a man named Haan visited the island, and over a period of thirty years he cultivated a bond with the Wyverns, and became the first Dragoon. Along with their Wyverns, the Dragoons were a formidable force.
The Empire, fearing the Dragoons, poisoned their water supply. The Wyverns died, and without them, the Dragoons could not resist the Empire's army. The sword and symbol of the Dragoons was known as the Excalibur and is given to Firion by Elina after she hears of Ricard's death. After doing this, she takes her son, Kain, and travels to places unknown.