Old Testament Manuscripts
The originals were probably written over the period 1400-400 BC.
The earliest fragments discovered to date are among the Dead Sea Scrolls: parts of Exodus and Samuel from ~250 BC.
The earliest complete book (Isaiah) comes from the same find, dating to ~125 BC.
The earliest complete copy of the whole OT, surprisingly, is a Greek translation, from ~AD 350.
The earliest complete Hebrew manuscript only goes back to about AD 950.