The Jews used Hebrew and the language of their faith.
And the center of worship was Jerusalem.
But over time, some persons were added to the Jewish faith who were not of Hebrew descent; many of these lived far from Jerusalem. They and their descendants began to prefer Greek (a language common among scholars) as their written language. A group of about 70 Greek speaking/writing Jewish scholars developed the Septuagint. This included some book written later than the other books, and written in Greek, not Hebrew.
The Hebraic Jews had some animosity towards the Greek Jews. They rejected these books written in Greek. They accepted only the earlier books written almost entirely in Hebrew.
This animosity carried over into the Christian faith. Some early Christians were formerly Hebraic Jews and some were formerly Greek-speaking Jews. A conflict between them is described in Acts, which led to the first Deacons being appointed.
The earliest Christians were rejected by the Jewish leaders of Jerusalem. Christianity spread far and wide. Very soon, the preferred version of Scripture was the Greek Septuagint. Only later did Latin become the vulgate (referring to the common version).
Protestants reject the additional books and portions of books in the Septuagint, but not in the Hebraic Jewish canon. Catholics accept the OT Scriptures in Greek as well as Hebrew (with some portions of some books in Aramaic).