Helga Johansen was a schoolmistress who suffered from mental illness, which prompted her to write. She was born and grew up in a merchant family in Copenhagen and is the sister of the painter Viggo Johansen, in whose home she was a beloved, unmarried aunt. She had a philosophical disposition, exchanged long letters with Georg Brandes, and contemplated existence and language until she made herself ill and was committed to a mental institution in 1883.
Under the pseudonym "Et Fruentimmer", she made her debut in 1896 with Rids, tre monologer. In 1900 her novel Hinsides, published under the pseudonym Hannah Joël came out, a work which with its constantly turning thoughts and monologues is a unique record of a psychotic world of experience. In her cultural philosophical publication Brev til Menneskene, 1903, insanity is depicted as insight and criticism of power.