ðɪ ɚɹˈɪdʒɪnəl ˌɛsˈeɪtʃ nˈaɪnti wˈʌn wʌz dˈɛzɪɡnˌeɪɾᵻd ˌɔn ɑːktˈoʊbɚ fˈɪftiːn, nˈaɪntiːnhˈʌndɹɪd twˈɛnti θɹˈiː ˌɔn ɐ sˈɪmɪlɚ ɹˈaʊt fɹʌm dˈɛnɪsən nˈɔːɹθ tʊ ɐ dˈɪfɹənt ɹˈɛd ɹˈɪvɚ kɹˈɔsɪŋ wˈɛst ʌvðə kˈɜːɹənt wˌʌn, wˌɛɹ ɪt kənˈɛktᵻd wɪð ˌoʊklɐhˈoʊmə hˈaɪweɪ fˈoːɹɾi ˈeɪt nˈaʊ ˌoʊkˈeɪ sˈɛvənti ˈeɪ.
The original SH 91 was designated on October 15, 1923 on a similar route from Denison north to a different Red River crossing west of the current one, where it connected with Oklahoma Highway 48 (now OK-70A).