The Yahweh-Alone Movement and the Fall of Israel and Judah

The Yahweh-alone movement wins notable victories thanks to sympathetic kings who try to stamp out idolatry. Religious reforms, however, are not enough to prevent foreign empires from encroaching upon the two kingdoms.

Why did Israel and Judah vacillate between the exclusive worship of Yahweh and a more tolerant worship of other Canaanite gods? How did the international situation influence religious debates within the kingdoms?