In 1943 Pope Pius XII issued an encyclical letter, Divino afflante Spiritu, which encouraged Roman Catholics to translate the Scriptures from the Hebrew and Greek texts, rather than from Jerome’s Latin Vulgate. As a result, a number of Dominicans and other scholars at the École Biblique in Jerusalem translated the scriptures into French. The product of these efforts was published as La Bible de Jérusalem in 1956.
Your question is a bit interesting, as biblical scholarship goes back before Pope Pius XII. However, there was a gap between what scholars were doing and what was happening “in the pew”. It was not in the least unusual for people to have a “home” bible. And it was not so much that people were discouraged from studying the Bible, as much as it was simply not a matter of focus.
That is not to say that people may not have been warned from trying to interpret the Bible (which is a bit different from not reading it) as the focus of many who knew their faith was still focused backward as seeing the Protestants as “heretics” and “wrong”, rather than seeing what we shared in common with the Protestants. And as a note, the Church does not consider the vast majority of Protestants as “heretics”, although heir founders may have been.
Keep in mind also that while there were lay theologians prior to Vatican 2, there were not many spread around, and there was far less information coming from the ones who existed; information directed to the “pew sitters” was little and far in between, Since Vatican 2, there have been many more individuals who have earned Masters and PhDs in Theology, and in particular, Scriptural Theology, and so there is a far greater amount of information directed to the laity, both in studies in themselves, and in programs for studying the Bible in groups. And that at least in part can be from the leadership which Pius XII and subsequent Popes have given us, as well as the documents of Vatican 2.
So the Jerusalem Bible, which came out first in French in 1956, arrived in the English speaking world in 1966, amid an almost explosive interest in Scripture, and Scripture scholarship.
The link in post #2 is worth reading (although a bit long). Also, one of the aspects of the Jerusalem Bible was the extensive footnotes, which helped readers to see interconnects which were simply unknown to readers prior to its publication.