Why did Jerome Translate Tobit and Judith?

Jerome translated the Hebrew Bible into Latin over a decade and a half beginning in about 390 c.e. With each translation he included a preface dedicating (in most cases) the translation to a friend or patron and defending his reliance on what he called the hebraica veritas (Hebrew truth) against his many detractors. This last feature of the prefaces proved necessary because by choosing the Hebrew text of the Old Testament as his base text, Jerome directly challenged the traditional position of the Septuagint within the church. The unpopularity of this move in some circles compelled Jerome repeatedly to justify his adherence to the Hebrew text. Similarly, in his Preface to Samuel and Kings (the “Helmeted Preface” or Prologus galeatus) he famously advocated the Hebrew canon as the Christian Old Testament and relegated all other books to the apocrypha. As part of this latter category, Jerome named six books outside the Jewish canon that were finding acceptance as fully canonical in some quarters and would much later receive the label “deuterocanonical,” these books being Tobit, Judith, Wisdom of Solomon, Sirach, and 1 and 2 Maccabees. In multiple ways Jerome sought to restore the Christian Old Testament to what he considered the original Hebrew text and canon.