The elves and men, through dust and rain, marched onward to Mordor, swords unsheathed and bows within an arm's reach. Then the orcs came out, and finally Sauron too, who killed Elendil, and lost the ring to Isildur. Isildur died, and the ring came to Deagol, who's dear friend Smeagol saw the ring, and murdered Deagol for possession of that ring. Smeagol took the ring into the mountains and let it possess him and slowly destroy him for centuries. Some say it was 500 years. Others say it was 5000 years. However, when Bilbo emerged from the mountain with that ring, much had changed that would not become apparent to the men for centuries. Yes, the elves probably knew of what would come, and those with palantir or foresight . . .