Tuhia he tohutoro mō tēnei wāhanga - I te mutunga o ngā pakanga i Āwherika, ka kitea e Afonso V he wāhi hōu mō te whawhai i te whenua tata o Castile. I te 11 o Tihema, 1474, ka mate a Kingi Henare IV o Kastila, kaore he tangata tane hei rangatira, kotahi anake tana tamahine, a Joanna. Heoi, i ruarua tana papa; i kii te korero ko tana wahine, ko Kuini Joan o Portugal (te tuahine o Afonso) he hononga ki tetahi rangatira ko Beltrán de La Cueva. Na te matenga o Henare i ara ake ai he pakanga o te rangatiratanga
Ko tētahi rōpū e tautoko ana i a Joanna, ko tētahi e tautoko ana i a Isabella, te tuahine o Henry. I whakatenatenahia a Afonso V ki te whakauru atu mo Joanna, tana tuahine. I whakaipoipo ia ki a ia, i kī ia ko ia te kingi o Castile, ā, i ārahi i ngā hōia ki te rangatiratanga. Na te whanaungatanga toto tata, me tatari te marena ā-ture ki te whakaaetanga a te pāpa.