The year is around 750 BC and Amos is called by God to prophesy against Israel in the Northern Kingdom during the reign of King Jeroboam II. God reveals his anger at Israel through visions to Amos, and Amos pleads for mercy on Israel's behalf.
Jonah ben Amitai is mentioned briefly in II Kings, where he delivered a short prophecy during the reign of King Jeroboam II (765-745 BCE) who restored the border of Israel from the entrance of Hamath unto the sea of the Arabah, according to the word of the Lord, the God of Israel which He spoke by the Lord of His servant Jonah ben Amitai (II Kg.
Jeroboam II had the good fortune to reign before Tiglath-Pileser III, King of Assyria (747-727 BCE), whose program of expansion built a mighty empire which eventually swallowed the Northern Kingdom of Israel in 722 BCE.
Jonah was a prophet from Gath-hefer in the Kingdom of Israel, then under the rule of Jeroboam II. Gath-hefer is a city of the northern tribe of Zebulun, as the text says: And the third lot came out in favor of the children of Zevulun according to their families, and the border of their inheritance was as far as Sarid ...
Jonah lives in the time of Jeroboam II (785-744 B.C.E), (13) not long before the Assyrian conquest of the Northern Kingdom of Israel and the exile of its people in 722 B.C.E.