Late 19th century; earliest use found in Charles Francis Keary (1848–1917), numismatist and writer. From mytho- + -poiesis, after Hellenistic Greek μυθοποίησις.
Definition of mythopoesis in US English:
mythopoesis
(also mythopoiesis)
nounˌmɪθə(ʊ)pəʊˈiːsɪs
The creation of a myth or myths; = "mythopoeia".
Origin
Late 19th century; earliest use found in Charles Francis Keary (1848–1917), numismatist and writer. From mytho- + -poiesis, after Hellenistic Greek μυθοποίησις.