The great bulk of these tablets appear near the end of this period and from 1 treasure‑trove:   the great library of Assurbanipal, the last great king of Assyria.  This collection was buried with his palace when Nineveh was destroyed in 612 B.C., and it reappeared in 1853 as a ditch full of tablets: about 20,000 in layers about 5 ft. deep.