Amos was one of the Twelve Minor Prophets. An older contemporary of Hosea and Isaiah, Amos was active c. 760-755 BCE during the rule of kings Jeroboam II of Israel and Uzziah of Judah. He was from the southern Kingdom of Judah but preached in the northern Kingdom of Israel. Amos wrote at a time of relative peace and prosperity but also of neglect of God's laws. He spoke against an increased disparity between the very wealthy and the very poor. His major themes of justice, God's omnipotence, and divine judgment became staples of prophecy. The Book of Amos is attributed to him.