Thorin Oakenshield walked into the library of the kingdom of Erebor. His father had sent him here to study. It was currently 2757 on middle earth and thorin was 11. The dwarven prince began scanning books about the great rings of power when he saw someone, a relatively short, elven girl.

There was a meeting going on between Thorin’s grandfather (the dwarven king of Erebor) and his father and King Thranduil of Mirkwood so there were a few elves in the kingdom right now.