How it was discovered
A young Bedouin shepherd, Muhammed edh-Dhib of the Ta'amireh tribe, threw a stone into a cliff opening near Khirbet Qumran while searching for a stray goat and heard pottery shatter. Inside were tall cylindrical jars containing linen-wrapped scrolls. Three scrolls reached the antiquities dealer Khalil Iskander Shahin ('Kando') in Bethlehem and were bought by Metropolitan Athanasius Yeshue Samuel of the Syrian Orthodox monastery in Jerusalem; four more went to Hebrew University archaeologist Eleazar Sukenik in late 1947. The cave itself was located and formally excavated by Roland de Vaux and G. Lankester Harding in early 1949.
Why it matters
1QIsaᵃ pushed the oldest known Hebrew manuscript of Isaiah back roughly a thousand years, from the Aleppo/Leningrad codices (c. 900–1000 CE) to the second century BCE — and the text proved substantially the same.
Source & further reading