The Lachish Letters or Lachish Ostraca, sometimes called Hoshaiah Letters, are a series of letters written in carbon ink in Ancient Hebrew on clay ostraca. The letters were discovered at the excavations at Lachish (Tell ed-Duweir).
The ostraca were discovered by James Leslie Starkey in January–February, 1935 during the third campaign of the Wellcome excavations. They were published in 1938 by Harry Torczyner (name later changed to Naftali Herz Tur-Sinai) and have been much studied since then. Seventeen of them are currently located in the British Museum in London, a smaller number (including Letter 6) are on permanent display at the Rockefeller Museum in Jerusalem, Israel.
The individual ostraca probably come from the same broken clay pot and were most likely written in a short period of time. They were written to Yaush (or Ya'osh), possibly the commanding officer at Lachish, from Hoshaiah (Hoshayahu), a military officer stationed in a city close to Lachish (possibly Mareshah). In the letters, Hoshaiah defends himself to Yaush regarding a letter he either was or was not supposed to have read. The letters also contain informational reports and requests from Hoshaiah to his superior. The letters were probably written shortly before Lachish fell to the Babylonian army of King Nebuchadnezzar in 588/6 BC during the reign of Zedekiah, king of Judah (ref. Jeremiah 34:7).