Kalma’s folk means the dead living in graves. Kalma means corpse or death.
They are described as corpses in decay, covered in mold, or as skeleton-like figures.
They are often portrayed as a family.
The underground world of the graveyards is called Kalma’s kingdom or Kalma’s mansions.
Didst thou come from Kalma’s kingdom,
From the castles of the death-land?
Haste thou back to thine own country,
To the Kalma-halls and castles,
To the fields with envy swollen,
Where contending armies perish.