He becomes king at age 12 years and reigns for 55 years.
(2 Kings 21:1; 2 Chronicles 33:1) Edwin Thiele has concluded that he commenced his reign as co-regent with his father Hezekiah in 697/696 BCE, with his sole reign beginning in 687/686 BCE and continuing until his death in 643/642 BC.
William F. Albright has dated his reign from 687 – 642 BCE.
Manasseh was the first king of Judah who would not have had a direct experience of a Kingdom of Israel, which had been destroyed by the Assyrians in c. 720 BCE and most of its population deported.
He re-instituted pagan worship and reversed the religious reforms made by his father Hezekiah; for which he is condemned by several religious texts.
He was married to Meshullemeth, daughter of Haruz of Jotbah, and they had a son Amon, who succeeded him as king of Judah upon his death.
After a reign of 55 years (for 10 of which he was co-regent with his father), the longest in the history of Judah, he died in c. 643 BCE and was buried in the garden of Uzza, the "garden of his own house" (2 Kings 21:17-18; 2 Chronicles 33:20), and not in the City of David, among his ancestors.
The biblical account of Manasseh is found in II Kings 21:1-18 and II Chronicles 32:33-33:20.
