I hear the year 10191 thrown around a lot for when Dune is set. I do not remember that exact number coming up, or if it did it was a BG (before Guild) year, not CE (our time) year. So I'm wondering if there is any canonical evidence for when Dune is set from our time?
The first book is indeed explicit that it take place in 10,191 AG (After Guild, not Before).
In particular, Appendix IV - "The Almanak en-Ashraf (Selected Excepts of the Noble Houses)" has death dates for (spoiler, I guess)
as that year.
Similarly, one of the chapter headings has a brief biography of
again with that year of death.
However as far as I know there is no canon timeline for when that maps to in CE.
: there is one in the Dune Encyclopedia, but that is explicitly not canon.
The year 10191 - when the story starts - is in B.G./A.G. notation, as per Terminology of the Imperium:
B.G.: idiomatic for Bene Gesserit except when used with a date. With a date it signifies Before Guild and identifies the Imperial dating system based on the genesis of the Spacing Guild’s monopoly.
Battle of Corrin takes place in 88 B.G., Butlerian Jihad is 210 B.G. - 108 B.G, and before that there was 11000 years of human decentralized space exploration period (as per Appendix II):
Mankind’s movement through deep space placed a unique stamp on religion during the one hundred and ten centuries that preceded the Butlerian Jihad.
There is also the need of subtracting difference between Solar Day and Standard Day length (about 20h/y), which comes to about 53 years (over 23400 years).
So, depending on accepted canon, 10191 A.G. is somewhere between 23350 A.D. (my proposition, based on Original Dune Canon only is 23389 A.D.) and 26500 A.D. Also, depending on the definition of space flight. Appendix mentions it in context of deep space, meaning interstellar, so there is still T.B.D. factor here, but I'm optimistic and say 2050.