Let's see:
"The Most Holy Roman Church firmly believes, professes and preaches that none of those existing outside the Catholic Church, not only pagans, also Jews, heretics, and schismatics can ever be partakers of eternal life, but that they are to go into the eternal fire 'which was prepared for the devil and his angels' (Mt. 25:41) unless before death they are joined with Her... No one, let his almsgiving be as great as it may, no one, even if he pour out his blood for the Name of Christ can be saved unless they abide within the bosom and unity of the Catholic Church." - Pope Eugene IV, 1441
What a "jerk".
Every Pope who has made a similar statement was referring to those who knew that the Catholic Church is the true Church and refused to enter it. This is what all Catechisms have taught on the subject.