Dagmar Johanne Amalie Overbye was born in Denmark on April 23, 1887 and by the 1910s was living in Norrebro, a working-class district of Copenhagen, taking in infants.
Baby farming in Denmark at the time was the same arrangement it was in England: an unmarried mother with no means and no legal alternative paid a lump sum to a woman who undertook to find the child a home. Overbye advertised, took the money, and killed the children, by strangling them, drowning them, or putting them in the stove. She burned the bodies in her tiled stove or buried them, and she killed one of her own.
Between 1913 and 1920 she is thought to have killed as many as twenty-five. Nine were established.
She was caught in 1920 when a mother, Karoline Aagesen, changed her mind within hours and came back for her daughter, and Overbye could not produce her. She was tried in 1921 in a case that gripped Denmark, and it was the first trial in Danish history at which women served on the jury.
She was convicted of nine murders and sentenced to death on March 3, 1921. It was commuted to life on May 25. She died in prison on May 6, 1929. The case led directly to Danish reform of the supervision of fostering and of the position of unmarried mothers, on the argument that the trade existed because the state had left them no other option.