Wikipedia explains why Jesuits used to do such wicked things…
“To understand the impetus behind these Jesuit efforts, one must take into account the widespread Catholic belief about baptism, current at that time. It would be centuries before the Catholic church would reconsider its glum appraisal of the chances of salvation for those not baptised into the Church. From this came the heroic efforts of missionaries to the detriment of native cultures, which few today could countenance.“
 “Lumen Gentium” (16).
– Wikipedia “Jesuit reduction”