• Doctor Thomas Stockmann, medical officer of the Baths.
• Mrs. Stockmann, his wife.
• Petra, their daughter, a teacher.
• Eilif
  Petra }their sons, thirteen and ten years old respectively
• Peter Stockmann, the doctor’s elder brother, Burgomaster^[5] and chief of police, chairman of the Baths Committee, etc.
• Morten Kiil,^[6] master tanner, Mrs. Stockmann’s adoptive-father.
• Hovstad, editor of the “People’s Messenger.”
• Billing, on the staff of the paper.
• Horster, a ship’s captain.
• Aslaksen, a printer.

Participants in a meeting of citizens: all sorts and conditions of men, some women, and a band of schoolboys.

The action passes in a town on the South Coast of Norway.