|Other names||Klaus Hakon Erik Westergaard|
|Hair color||Dark brown|
|Eye color||Brown, right is cloudy|
|Portrayed by||James Barbour|
|First appearance||Frozen: The Kingdom of the Sun|
"For the good of the kingdom."
King Klaus Hakon Erik Westergaard of the Southern Isles is the reigning monarch of the Southern Isles, and eldest of the late King Soren and Queen Helena's thirteen sons. He is voiced by James Barbour as an adult.
Klaus is shown to be an aloof and often austere man, who rules his country (and his twelve younger brothers) with an iron fist and a mind clear of sentiment. His primary focus is the wellbeing and prosperity of the Southern Isles, willing to go as far as to resorting to blackmail and scare tactics to ensure them. Although rarely one to display emotions, Klaus is infuriated by acts of disobedience and any questioning of his authority, and will even react with violence if provoked enough.
The King devotedly believes all of his subjects exist to serve a role in the kingdom's productivity, and all other aspects are insignificant in comparison. For example, Klaus has assigned each of his brothers, save for Hans, to a position of authority within the Southern Isles, to the point of all the highest seats of government are occupied solely of the Westergaard family.
Klaus is a tall and imposing man in his late thirties. His features greatly resemble those of his father, King Soren; He has fair skin, dark brown, almost black, hair tied back in a short ponytail and a thick beard. His eyes are brown, but his right eye is cloudy. Klaus is reasonably good-looking, but his ever present grim expression makes him seem more intimidating than anything else.
Like his brothers, Klaus has a preference for fine, expensive clothes. He wears a black shirt, beige-white pants, a forest green jacket with gold details and epaulets, a burgundy cravat and black boots. His kingly regalia consists of an exquisite gold crown decorated with red and white jewels, and a gold mantle.
- Klaus' name is a Danish variant of Nicholas, which comes from the Greek word for victory. Klaus could be considered "victorious" as the prince who inherited the Southern Isles' throne.
- It can be assumed that Klaus is 39 years old, as Hans claims that he is "pushing forty."