Question: During what decade did J.R.R. Tolkien use mythopoeia in his literary works?
Sentence (from "The Silmarillion"): The Silmarillion is a collection of mythopoeic works by English writer J. R. R. Tolkien, edited and published posthumously by his son, Christopher Tolkien, in 1977, with assistance from Guy Gavriel Kay.
Relevant evidence: Yes