This is the year 10,191 (ten thousand, one hundred and ninety one).
In the year 10,191, the Known Universe (called the Imperium), is ruled by a Padishah Emperor. In this year, it is the 81st Padishah Emperor Shaddam IV of House Corrino. The Universe is ruled by him, The Spacing Guild: an organization that controls the banking of the Universe and controls all transportation in the Universe, and the Landsraad: the council of Great Houses, families that govern and rule the major planets of the Universe.
Under the Universal agreement called the Great Convention, no Great House is allowed to use atomics against any live target. There is also the Bene Gesserit Sisterhood, a group of witches who, for 90 generations, have manipulated the blood lines of the Great Houses in hopes of a mother giving birth to a super being whom they plan to control.
Above all, there is the spice melange: a drug that creates prescience, that extends life, that expands consciousness. The spice is vital to space travel, which is used by the Spacing Guild. The spice, however, exists on only one planet in the entire Universe: the planet Arrakis, also known as Dune.