Þórbergur Þórðarson (Thorbergur Thordarson) (Hali í Suðursveit, 12 March 1888/1889 – Reykjavík, 12 November 1974) was an Icelandic author and Esperantist.
An ironist, satirist, volatile critic, and ground-breaking achiever in experimental auto-fiction, Þórbergur arguably remains among Iceland's most beloved 20th century authors.
Þórbergur was an autodidact. As recounted in his largely autobiographical works, Íslenzkur aðall (1938) and Ofvitinn (1940), Þórbergur lived in poverty for much of his youth and early adulthood and could not afford secondary or higher education.
In January 1934, Þórbergur wrote a series of essays for the socialist daily Alþýðublaðið, titled "The Nazis' Sadistic Appetite" ("Kvalaþorsti nazista"). Iceland's public prosecutor filed charges against Þórðarson for supposedly offensive clauses in the article, one of which labelled Adolf Hitler "a sadist". The Supreme Court of Iceland agreed with the prosecutor and found the author guilty of "derogating a foreign nation". The court sentenced Þórbergur to pay a fine of 200 krónur.
The relatively little of Þórbergur's work which has been translated into English consists mainly of fragments from his larger works. Portions of Íslenzkur aðall (1938) were published as In Search of My Beloved in 1967. In recent years, Professor Julian Meldon D'arcy has translated a fragment from Bréf til Láru (1924) as a short story, titled "When I got pregnant", as well as the first full book to appear in English translation: The Stones Speak (2012), Þórbergur's childhood memoirs, originally published as Steinarnir tala in 1956.
On 30 June 2006, Þórbergssetur, a museum and cultural center in Hali, Suðursveit, Iceland devoted to Þórbergur's work, was inaugurated.