A very long time ago, some very rich dwarves (some of Thorin's ancestors) got driven out of the North, and ended up moving to a mountain, taking their riches with them. Life was great; nobody was poor. No one ran out of money, and nobody ever had to worry about anything. But, a dragon found out about their gold, and immediately wanted it. The dragon, named Smaug, decided to go to the mountain, to take the dwarves' gold. He breathed fire, and set fire to many things; destroying homes, and killing many people. He scared people out of their homes, and went inside them, taking their gold. The warriors tried to stop Smaug, but he ended up killing almost all of them. Only a very small amount of people survived the attack, Thorin's grandfather, and father. Smaug (of course) ended up winning the battle, and took all of the gold he could get with him. He had so much gold, that he even slept on it.