documentary (adj.) c.1810, “pertaining to documents,” from document + -ary. Meaning “factual, meant to provide a record of something” is from 1926, from Fr. film documentarie (1924). The noun (short for documentary film) is attested from 1935. Docudrama is a 1961 coinage. Until MUBI allows me to arrange these chronologically they will remain disordered.