Kammala wannan magana: Doria ya yi karatun falsafa da tauhidi a Spain wanda aka inganta shi zuwa Cardinal a kan Sarki Felipe II na Spain. Da zarar sarki Philip II ya mutu, an nada shi kardinal deacon, yana da shekaru 31, a cikin taron na Yuni 9, 1604. An ba Doria izinin karɓar umarni mai tsarki a waje da ranakun Ember, 9 ga Disamba, 1604. Ya halarci duka a watan Maris-Afrilu 1605 papal conclave, wanda ya zabi Paparoma Leo XI, kuma a cikin
A watan Mayu na shekara ta 1605 ne aka zaɓi Paparoma Bulus na Biyar.