[1] He pioneered psychological literature with techniques of stream of consciousness and interior monologue, and influenced authors such as Thomas Mann, Franz Kafka, Maxim Gorky, Stefan Zweig, Henry Miller, Hermann Hesse, John Fante, James Kelman, Charles Bukowski and Ernest Hemingway.

[2] Isaac Bashevis Singer called Hamsun "the father of the modern school of literature in his every aspect—his subjectiveness, his fragmentariness, his use of flashbacks, his lyricism.

He argued that the main object of modernist literature should be the intricacies of the human mind, that writers should describe the "whisper of blood, and the pleading of bone marrow".

[5] Hamsun is considered the "leader of the Neo-Romantic revolt at the turn of the 20th century", with works such as Hunger (1890), Mysteries (1892), Pan (1894), and Victoria (1898).

[6] His later works—in particular his "Nordland novels"—were influenced by the Norwegian new realism, portraying everyday life in rural Norway and often employing local dialect, irony, and humour.

[11][12][13] Hamsun's last book, On Overgrown Paths, authored in semi-imprisonment in Landvik, concerned his treatment and rebuttal of accusations of his mental ineptness.

At nine Knut was separated from his family and lived with his uncle Hans Olsen, who needed help with the post office he ran.

Olsen used to beat and starve his nephew, and Hamsun later stated that his chronic nervous difficulties were due to the way his uncle treated him.

For the next five years he did any job for money; he was a store clerk, peddler, shoemaker's apprentice, sheriff's assistant, and an elementary-school teacher.

[18] He spent several years in America, traveling and working at various jobs, and published his impressions under the title Fra det moderne Amerikas Aandsliv (1889).

Working all those odd jobs paid off,[19] and he published his first book: Den Gaadefulde: En Kjærlighedshistorie fra Nordland (The Enigmatic Man: A Love Story from Northern Norway, 1877).

The semiautobiographical work described a young writer's descent into near madness as a result of hunger and poverty in the Norwegian capital of Kristiania (modern name Oslo).

A theme to which Hamsun often returned is that of the perpetual wanderer, an itinerant stranger (often the narrator) who shows up and insinuates himself into the life of small rural communities.

This connection between the characters and their natural environment is exemplified in the novels Pan, A Wanderer Plays on Muted Strings, and the epic Growth of the Soil, "his monumental work" credited with securing him the Nobel Prize in Literature in 1920.

[25] After Hitler's death, he published a short obituary in which he described him as "a warrior for mankind" and "a preacher of the gospel of justice for all nations".

Deeper explanations involve his contradictory personality, his distaste for hoi polloi, his inferiority complex, a profound distress at the spread of indiscipline, antipathy toward the interwar democracy, and especially his Anglophobia.

For this new edition, all of Hamsun's works underwent slight linguistic modifications in order to make them more accessible to contemporary Norwegian readers.

[34] Along with August Strindberg, Henrik Ibsen, and Sigrid Undset, Hamsun formed a quartet of Scandinavian authors who became internationally known for their works.

Hamsun pioneered psychological literature with techniques of stream of consciousness and interior monologue, as found in material by, for example, Joyce, Proust, Mansfield and Woolf.

"[36] Hamsun wrote several newspaper articles in the course of the Second World War, including his notorious 1940 assertion that "the Germans are fighting for us, and now are crushing England's tyranny over us and all neutrals".

[40] Nevertheless, a week after Hitler's death, Hamsun wrote a eulogy for him, saying “He was a warrior, a warrior for mankind, and a prophet of the gospel of justice for all nations.”[33] Following the end of the war, angry crowds burned his books in public in major Norwegian cities and Hamsun was confined for several months in a psychiatric hospital.

Hamsun was forced to undergo a psychiatric examination, which concluded that he had "permanently impaired mental faculties," and on that basis the charges of treason were dropped.

Instead, a civil liability case was raised against him, and in 1948 he had to pay a ruinous sum to the Norwegian government of 325,000 kroner ($65,000 or £16,250 at that time) for his alleged membership in Nasjonal Samling and for the moral support he gave to the Germans, but was cleared of any direct Nazi affiliation.

Among other things Hansen stated: "If you want to meet idiots, go to Norway," as he felt that such treatment of the old Nobel Prize-winning author was outrageous.

Remodernist filmmaker Jesse Richards has announced he is in preparations to direct an adaptation of Hamsun's short story The Call of Life.