ɪn nˈaɪntiːnhˈʌndɹɪd sˈɛvəntˌiːn, bˈɑːɹwɛl wʌz mˌeɪd ɐtˈɜːnidʒˈɛnɚɹəl ʌv sˈaʊθ ɔːstɹˈeɪliə ænd mˈɪnɪstɚ fɔːɹ ˈɪndʌstɹi ɪn ˈɑːɹtʃɪbˌɔːld pˈiːks kˈæbᵻnət ænd wʌz fˈoːɹst tə dˈiːl wɪððə dɪtˈiəɹɪɹˌeɪɾɪŋ ɹᵻlˈeɪʃənʃˌɪp bᵻtwˌiːn ðɪ ˈɜːbən ænd ɹˈʊɹɹəl kənstˈɪtʃuːənsiz ʌvðə lˈɪbɚɹəl jˈuːniən, wˌɪtʃ wˈɜːsənd wɪððə kɹiːˈeɪʃən ʌvðə kˈʌntɹi pˈɑːɹɾi ɪn nˈaɪntiːnhˈʌndɹɪd nˈaɪntiːn, tˈeɪkɪŋ mˈɛnɪəv ðə lˈɪbɚɹəl jˈuːniənz səpˈoːɹɾɚz wɪð ɪt.
In 1917, Barwell was made Attorney-General of South Australia and Minister for Industry in Archibald Peake's cabinet and was forced to deal with the deteriorating relationship between the urban and rural constituencies of the Liberal Union, which worsened with the creation of the Country Party in 1919, taking many of the Liberal Union's supporters with it.