prehistoric culture vs prehistory

prehistoric culture and prehistory both are nouns.

Word	Noun	Adjective	Verb	Adverb
prehistoric culture	Yes	No	No	No
prehistory	Yes	No	No	No

As nouns, prehistoric culture and prehistory are synonyms defined as:

prehistoric culture and prehistory: the time during the development of human culture before the appearance of the written word

prehistoric culture (noun)	prehistory (noun)
the time during the development of human culture before the appearance of the written word	the time during the development of human culture before the appearance of the written word