Final answer:
King Manasseh was the most wicked king of Judah, known for his 52-year reign that was characterized by the reintroduction of idolatry and foreign cults, which starkly contrasted the religious reforms of his father, King Hezekiah.
Step-by-step explanation:
The most wicked king of Judah, despite his long and seemingly peaceful reign of 52 years, was King Manasseh. This is indicated in the biblical narrative, where Manasseh is depicted as having reversed the religious reforms of his father, King Hezekiah, by restoring polytheistic practices and shrines. This relentless devotion to idolatry and introduction of foreign religious traditions provoked the condemnation of the biblical authors.
Under the rule of King Solomon, Judah experienced wealth and prosperity, thanks largely to its position on key trade routes and the presence of gold mines. However, widespread resentment developed among the Hebrews over Solomon's heavy taxation and labor demands, which eventually led to the division of the kingdom. King Manasseh's wickedness was interpreted as exacerbating the spiritual decline, contrasting the pious efforts by other kings like King Hezekiah who sought to purify worship and maintain fidelity to the covenant with Yahweh.
During the era known as the united monarchy, settled under kings like Saul, David, and Solomon, Judah established itself though smaller in scale compared to neighboring powers. King Manasseh's rule, which included idolatrous practices, was seen as one of the low points in Judah's spiritual history, marking him as a notably wicked leader compared to his forebears and successors.