mythopoeia
noun
mytho·poe·ia ˌmi-thə-ˈpē-ə 
: a creating of myth : a giving rise to myths
mythopoeic
ˌmi-thə-ˈpē-ik
adjective or less commonly mythopoetic
ˌmi-thə-pō-ˈe-tik
or mythopoetical ˌmi-thə-pō-ˈe-ti-kəl
Word History
Etymology
borrowed from Greek mȳthopoiía, from mŷthos "utterance, tale, myth" + -o- -o- + -poiia (from poieîn "to make, produce, do" + -ia -ia entry 1) — more at poet
First Known Use
1846, in the meaning defined above