When was The Worlds of Frank Herbert created?

The "Worlds of Frank Herbert" is not a specific work or entity, but rather a general term referring to the universe and settings created by Frank Herbert in his various works.

However, we can pinpoint the specific creation dates of his most famous works:

* Dune: First published in 1965.

* Dune Messiah: Published in 1969.

* Children of Dune: Published in 1976.

* God Emperor of Dune: Published in 1981.

* Heretics of Dune: Published in 1984.

* Chapterhouse: Dune: Published in 1985.

Therefore, the "Worlds of Frank Herbert" were created and expanded over a period from 1965 to 1985.