The Landsraad Council met regularly, and provided a forum within which Great Houses could relate with one another, to either negotiate trade agreements, create alliances or conduct kanly, the formalised processes of vendetta, or feud. It was also supposed to protect the Great Houses from being singled-out by the Imperial House and eliminated by it.
The Landsraad Council did not come into play with the destruction of House Atreides, however, in the Original Dune due to the jealousy and envy that the other Houses had for the popularity of Duke Leto Atreides.
In terms of military strength, all the Great Houses, were they to unite through the Landsraad, would supposedly have been a match for the Imperial Sardaukar forces.
Upon the ascendancy of House Atreides to the Imperial Throne, the Landsraad saw a reduction in its power, but the continuation of the Great Houses meant the body remained in place for at least several hundred years into the reign of Leto Atreides II, the God Emperor.
The Landsraad was governed by the High Council. It presided over issues such as the forms of Kanly, and whether certain Houses should be banished for breach of the Great Convention.
Motions were passed by a vote. Great Houses maintained the "lion's share" of the vote, while the Imperial House also had a powerful vote. Minor Houses had a lesser vote. However, even the Emperor had to answer to the High Council on some issues.
Behind the Scenes
Great Houses continued to exist after the death of Leto II, even during the time the Lost Ones returned from The Scattering. However, it is not known whether the Landsraad continued to exist during this time. Regardless, neither the Landsraad nor the Great Houses were central to the stories of the later Dune novels by Frank Herbert.
The word Landsraad means literally "Land Council". The word exists in several Scandinavian languages, but is now spelled Landsråd; until the spelling reform of 1948 it was still written as Landsraad in Danish. In Dutch or Afrikaans the word would also be Landsraad, but Herbert did borrow the word from Scandinavian. When asked, he defined the Landsraad thus:
Q: In the novel Dune, what is the Landsraad?
Herbert: Well, Landsraad is an old Scandinavian word for an assembly of landowners. It's historically accurate in that it was an assembly and the first meetings of the legislative body — an early one, yes. The Landsraad — it's the landed gentry.
- Vertex Interviews Frank Herbert, Interviewer: Paul Turner, October 1973, Volume 1, Issue 4