Greys is the homeland of Prince Herbert. It is ruled by a king, and Herbert is the prince of the land. Its exact location is unknown but based on interactions between the prince, princess, and the witch, it appears to be located near the Sovereignty of Serenia north of the Kingdom of Daventry.
Herbert and Alicia were taking a stroll in the Woods of Serenia when they encountered the witch. Herbert refused the witches advances and was banished to the woods of a faraway land, Alicia was transformed into a tree, and her heart was stolen. He later returned to Serenia, searching everywhere for her, but could not find her. After they were reunited, both left the country, and returned to Herbert's home to live happily ever after.
This may have been the neighboring land where Crispin attended to an emergency. While there he did some asking around, and found out that Alexander, had the dubious distinction, of turning Mordack's brother, Manannan, into a cat some time back. He also discovered, that Castle Daventry and Graham's family were miniaturized and imprisoned inside a glass bottle. He did some research and found the spell for turning everything back to normal. Perhaps the land is even located near Harlin's former castle in the North (or in Serenia's current configuration to the east or northeast).
It may also be one of the western and southern kingdoms which the people of Daventry fled to to escape the destruction of the Three-headed dragon. There are the many kingdoms the continent is divided into, most of them small and only a day or three's journey by foot in extent. These fiefdoms sometimes war with each other for reasons only their rulers care about, and shrink or grow depending on their martial fortunes. They seemingly come and go with the seasons, and few are remembered after their passing.
Behind the scenesEdit
Greys originates out of the King's Quest Companion. Based on medieval naming conventions it could be property (manor or castle) or even a surname (or both).
Gray (grey) is a relatively rare surname, shared by the Scots and Irish. In England it of typically Norman origin, stemming from the town of Grayes, France.
Depending on the version of KQ5 story the prince was banished to a far away land or the woods outside the Dark Forest, which is not that far away.
On the other hand based on information in The Official Book of King's Quest, Greys maybe a country that lies east or northeast of Serenia towards the Great Mountains. It says the couple left the country, and end game they walk off to the east.