mythology vs assemblage

mythology and assemblage both are nouns.

Word	Noun	Adjective	Verb	Adverb
mythology	Yes	No	No	No
assemblage	Yes	No	No	No

As nouns, assemblage is a hypernym of mythology; that is, assemblage is a word with a broader meaning than mythology:

mythology: myths collectively; the body of stories associated with a culture or institution or person
assemblage: several things grouped together or considered as a whole

Other hypernyms of mythology include accumulation, aggregation, collection.

mythology (noun)	assemblage (noun)
the study of myths	the social act of assembling
myths collectively; the body of stories associated with a culture or institution or person	a system of components assembled together for a particular purpose
	a group of persons together in one place
	several things grouped together or considered as a whole