Rubuta ci gaba don wannan sakin layi - Bayan karatun a Kwalejin Eton, an ba Thorpe izini a cikin Sojoji a ranar 8 ga Satumba 1897 a matsayin Laftanar na 2 a cikin Argyll da Sutherland Highlanders. An ba shi mukamin Laftanar a ranar 16 ga Yuli 1899 kuma ya yi aiki a Yaƙin Boer na biyu; da rauni, ya karɓi Sarauniya da Sarki na Afirka ta Kudu tare da ƙuƙwalwa don sabis a yakin Modder River da Pandaardeberg
, da kuma a Transvaal da Afirka ta Kudu (1901 da 1902). A ranar 15 ga Oktoba, 1901, an tura shi a matsayin Jami'in Ma'aikata.