The first possible situation places Obadiah around 845 BC in the midst of a brutal uprising by the nations surrounding Judah. The Philistines and their allies were attempting to sack Jerusalem, a rarity in antiquity. The Edomites were involved up to the point that as a neighboring nation, they did not even lift a finger to help the Israelites in their struggle. In fact, Obadiah states that they were complicit in collaborating with the demise of Jerusalem. For this reason, he prophesies about their coming doom that would happen after another sacking of Jerusalem around 586 BC where Babylon carried off the Israelites and scattered the Hebrews. Edom does have record of a rebellion against King Jehoram in 2 Kings 8:20-22. The history between these two nations of conflict is long and contains many such skirmishes.
The second possible situation focuses in on the sacking of Jerusalem by the Babylonians in 586 BC. Instead of coming to the aid and rescue of the Hebrews, the Edomites even helped to ransack the city and supported the entire endeavor. In the near future, the people of the Negeb. Nabonidus has a possible reference in his chronicle that details his burning and pillaging of the land of Edom in 552 BC, shortly after Jerusalem�s fall to the Babylonians in 586 BC. This would be the fulfillment of Obadiah�s prophecy.