Nyorai kuenderera mberi kweiyi ndima - Akapihwa basa semukuru wechiuto muna 1793, uye akasimudzirwa kuva kaputeni muna 1794, akashanda mumushandirapamwe wa1808-9 muPeninsular War, saMajor mu32nd Regiment, uye aivepo muhondo dzeRoliça
, Vimiero, uye Corunna. Johnson akabva apinda mubasa reWalcheren expedition muna 1809. Muna 1810 akava lieutenant-colonel mu 3rd Ceylon Regiment.