From 1957 until 2002, he published both fiction and non-fiction texts which include novels, poems, essays, a biography, and manuscripts for cartoons and animated films.

[2] Jensen completed three years of high school but only lasted a couple of days at university as he didn't like the quiet polite lectures and so gave it up.

[2] In 1954 Jensen flagged down a car on Majorstua Street in Oslo containing 19 year old Marianne Ihlen and invited her to a party.

Niels Christian Brøgger's review in the 12 December 1955 edition of the Nationen newspaper commented: [2] Axel Jensen does not write for a popular audience, and his mystical language will probably not be understood or appreciated by many.

Jensen was aggressive when he became drunk and at one party pushed his way into the room where Ihlen was sleeping and made her watch as he took a knife, spread his hand out on a kitchen table and stabbed it three times.

It was reviewed by over 30 Norwegian newspapers and highly praised by a number of literary critics with Kjølv Egeland of the Vinduet magazine commenting that "Here is one of the year's most sensational works of fiction.

"[2] In mid-November the reunited couple over her parents' objections departed by train for Greece with plans to be away for a year, with Jensen intending to spend the time writing.

Ihlen remained in hospital for a week recovering and it wasn't until December that they reached Athens where they stayed with their friends Per and Else Berit who had moved there the year before.

Jensen had originally intended that they rent an apartment in Athens, but their friends suggested they could live more cheaply on the island of Hydra, which was three hours away by ferry.

After visiting Delphi the couple drove down to Erminoni in the Peloponnese where their landlady at the place they stayed allowed them to park their car in her garden.

Ihlen remained on Hydra when it was necessary for Jensen to travel back several times to Norway to capitalize on the success of Ikaros – ung mann i Sahara.

[2] She subsequently found work as a cook on a chartered schooner, by the end of which Ihlen returned to stay with Per and Else Berit in Athens, who observed that the experience had transformed her into a serene and more confident person.

[2] With the novel printed and approaching its publishing date in 1959 Jensen and a by now pregnant Ihlen travelled to Oslo, where both were able to catch up with family and friends.

While the critic for the Morgenbladet newspaper considered it utterly devoid of artistic value, the critic for the Arbeiderbladet newspaper wrote:[2] A profound, bleeding earnest and an extravagant desperation and joie de vivre shines through Axel Jensen's new novel.The novel was such a success in Norway that it was translated into English and published in 1962 with the title A Girl I Knew.

The success of the novel allowed Jensen to travel in October with Ihlen, Per and Else Berit to Stockholm where via friends they purchased a Karmann Ghia.

Soon after Amlin was badly injured when she crashed Jensen's Karmann Ghia near Athens and was flung out of the car, breaking many bones and developing gangrene, which required amputation of a thumb.

Jensen allowed Ihlen to live in the house on Hydra and following their formal divorce a year later transferred ownership to her and their son.

[7] After taking Amlin back to America Jensen travelled around Mexico with his friend John Starr Cooke, experimenting with psychedelic drugs and catching malaria before returning to Hydra in the summer of 1960.

As he grew older, he developed psychiatric problems and from 1979 onwards spent a large part of his adult life being institutionalized in Norway.

The novel is about a young man searching for meaning in his life who travels to Greece, where he meets Cecilie, a Danish student with whom he has a relationship.

The plan was soon put into action, and Jensen became the front figure in a project which later developed into the Oslo International Poetry Festival (OIPF), occurring in 1985 and 1986.

Before the public health service provided the help he needed, private funding to pay for nursing was arranged by his close friends, including Leonard Cohen.

These novels include Icarus: A Young Man in Sahara (1957) (a new 1999 edition is illustrated by Frans Widerberg), A Girl I Knew (1959), and Joacim (1961).

Some critics have argued that these early novels are influenced by Beat authors like Jack Kerouac, Allen Ginsberg, and William Burroughs.

Later, Jensen departed from the realism in his early novels and began to move in a new direction by writing science fiction, poems, essays, and manuscripts for cartoons.

In this experimental phase, he produced manuscripts for the psychedelic comic-strip Doctor Fantastic (published in the newspaper Dagbladet between March and July 1972), the science fiction comic strip collage Tago (1979), the animated movie Superfreak (1988), and a manuscript for a comic novel which is a caricature-rendering of the life of the French playwright and founder of pataphysics, Alfred Jarry.

With these novels, Jensen created a dystopian vision of the future, much in the tradition of Aldous Huxley, George Orwell, and Ray Bradbury.