I te tau 1940 i whakahaua e Horrocks tētahi patationa i te Pakanga o Wīwī, te wā tuatahi i mahi ai ia i raro i a Bernard Montgomery, te rangatira Ingarangi tino rongonui o te pakanga. I muri mai ka kitea e Montgomery ko Horrocks tetahi o ana rangatira tino kaha, ka tohua ia hei rangatira mo nga roopu i Awherika ki te Raki me Uropi
He aha? I te 1943, i whara kino a Horrocks, neke atu i te kotahi tau ki te whakaora i mua i tana hokinga mai ki te whakahau i tetahi roopu i Uropi. Ko te mea pea ko tenei wa i waho o te mahi i kore ai ia e whakatairanga; ko ana rangatira o te ope taua i Awherika ki te Raki, ko Oliver Leese me Miles Dempsey, i haere ki te whakahau i te taumata ope taua me runga ake. Ko te whara a Horrocks i haere tonu ki te kino ki tona hauora, a, i arahi ki tana reti wawe mai i te ope i muri i te pakanga.