The Medes and Persians to the north had now become a formidable power,
and in 540 the Persian king, Cyrus, marched against Babylon, and under
its walls defeated Nabonidus, who fled to Borsippa, south of Babylon.
The capital was held by a son of Nabonidus, who had been made co-king
with his father,--Belshazzar. The revelries of this sovereign during the
siege, the handwriting on the wall, and his death the same night, are
given in the scriptural narrative of Daniel. The Babylonian Empire fell
in 538 B. C., and became a province of the Persian Empire. The site of
the great city of Babylon is now a marsh, formed by inundations of the
river, due to the destruction of the embankments and the choking up of
the canals.