Of the Austroasiatic languages, only Vietnamese, Khmer, and Mon have lengthy, established presences in the  historical record.
ʌvðɪ ˌɔːstɹoʊsɪˈæɾɪk lˈæŋɡwɪdʒᵻz, ˈoʊnli vˌiːɛtnəmˈiːz, kmˈɪɹ, ænd mˈɑːn hæv lˈɛŋθi, ɪstˈæblɪʃt pɹˈɛzənsᵻz ɪnðə hɪstˈɔːɹɪkəl ɹˈɛkɚd.