Rubuta ci gaba don wannan sakin layi - An ba shi izini a matsayin mai bin sawu a 1793, kuma an ba shi mukamin kyaftin a 1794, ya yi aiki a cikin kamfen na 1808<unk>9 a cikin Yakin Peninsular, a matsayin Manjo a cikin Rukunin na 32, kuma ya kasance a yakin Roliça
, Vimiero, da kuma Corunna. Johnson sa'an nan kuma ya yi aiki ta hanyar Walcheren expedition a 1809. A cikin 1810 ya zama laftanan-kolonel a cikin Rundunar Ceylon ta 3.