Queen Adelaide of Trigonia, known fully as Adelaide Guttsen-Alzabeth and born originally as Princess Adelaide of Selathon, is the third child and second daughter of the heir apparent to the Selathite throne, Prince Dominic, and his wife Princess Felicity, herself a member of the now dethroned Gaulean royal family. Adelaide is forty-four years of age, and married to King Honoratas II of Trigonia.

Adelaide was born the third child and second daughter, being two years younger than Prince Frederic, second in line to the throne of Selathon, one year younger than Princess Alexandra, and two years older than Prince Cameron. Adelaide became married at fourteen to the then heir apparent to the throne of Trigonia, who became the second Honoratas to become King of Trigonia, the first being his father. Adelaide first gave birth at fifteen, to a daughter by the name of Mariana.

Since then, Queen Adelaide has given birth to many more children. At sixteen she gave birth to Princess Antonella, at eighteen Princess Florencia, at nineteen her first son and heir apparent, Prince Terciero, at twenty-three her second son, Prince Oliverios, at twenty-five Princess Ximena, and finally at twenty-seven Prince Silverio.

It is known that Queen Adelaide has a passing friendship with her oldest brother Frederic, though keeps in much closer correspondence with her younger brother Cameron, and is distant with her only sister Alexandra. Her second son Oliverios is ambassador to Selathon, yet Queen Adelaide does not accompany him on his visits, instead preferring the comforts of her happy marriage.