The Library of Congress recently acquired a fragment of a Torah scroll dating to around the year 1000 CE. While it is not the single oldest such object extant, it is among the oldest, as Gary Rendsburg writes:
Readers . . . are likely aware of the approximately 220 biblical manuscripts from among the Dead Sea Scrolls, dating from the 3rd century BCE to the 1st century CE, along with the related documents from Masada, Naḥal Ḥever, Wadi Murabba‘at, and other sites, which date to the 1st and 2nd centuries CE. But what about the ensuing centuries, until we reach the date of the Library of Congress portion at approximately 1000 CE? What scrolls, or portions of scrolls, do we possess?
The oldest document is the Ein Gedi scroll, which was recently digitally “unrolled” through remarkable micro-CT scanning, revealing the text of Leviticus 1-2. Archaeological evidence suggests the date of the Ein Gedi synagogue [where it was found] is approximately 500 CE, but carbon-14 testing reveals that the scroll itself is much older, dating to ca. 300 CE. The scroll was found in the Torah niche of the Ein Gedi synagogue during excavations in 1970, so we may conclude that it was used for the liturgical reading of the Torah. Then, as now, Torah scrolls were sometimes used for centuries.
But the Ein Gedi scroll commences with a blank sheet, so we can be certain that this was not a complete Torah scroll but rather contained one, two, or three books only (that is, Leviticus only, or Leviticus and Numbers, or at most Leviticus-Numbers-Deuteronomy). I mention this because it relates to a parallel question: at what point did Torah scrolls come to contain all five books of the Pentateuch? There is no definitive answer to this question, but the blank sheet offers a clue. . . . The Ein Gedi scroll shows that by the 4th century CE there was not yet a requirement or custom that all five books of the Pentateuch be united into a single scroll. . . .
Next in age come the London and Ashkar-Gilson sheets, which derive from the same scroll, dated ca. 700 CE, [followed by] the fascinating Florence manuscript, a palimpsest [or book written on reused parchment]. The overtext is a Greek manuscript, dated to the 13th century CE, but much of the undertext in the second half of the manuscript is made up of sections of six old Torah-scroll sheets, dated to the 10th century CE, cut up and reused for the production of the overtext.