The Second Great War and other stories
The Compact is an ancient unwritten understanding between the gods not to interfere directly with mortal lives, as this tends to end in thousands of mortal deaths and less power all around (do not forget that the gods are dependent upon their mortal worshipers.) This “understanding” has the power of a law that has been ingrained into the gods since before the Age of Elves (see Calendar.)
This law has only been broken three times.
The last time the Compact was broken was during the War of the Burning Moon, only a few years ago. Over the course of fifteen terrifying hours, the gods destroyed one-third of the surface of the moon, and the entire country of Barovia, which was merely one side’s meeting ground. The goddess Anora began this fight, and in a stunning turn of events was not censured for it, instead gaining greater power.
The second time the Compact was broken was when the gods Bahamut and Tiamat began fighting each other for supremacy, and accidentally shifted to the Material Plane. The fallout from their struggle scoured the Southern Continent and turned most of it into a desert.
The first time the Compact was broken was shortly after the end of the First Era, when the hobgoblins attempted to exterminate the orcs and giants living in their new home. Gruumsh personally intervened, and the resulting escalation left the North a frozen wasteland instead of the breadbasket it had been, and left barely ten thousand orcs scattered across the face of the world.