Ruben Oskar Auervaara

Ruben Oskar Auervaara (until 1935 Jansson, from 1952 to 1959 Risto Oskari Karnas, from 1959 Erik Kristian Jansson, born 4 September 1906 – died 26 May 1964) was a notorious Finnish conman and thief. He became famous by cheating money from women he met through newspaper announcements, by pretending to intend to marry them. His surname has become an archetypal name in the Finnish language, meaning a deceptive charming trickster.

Auervaara spent 26 years of life in various prisons.