Thorin II was the son of Thráin II, grandson of Thrór, the brother of Dís, and the uncle of Kíli and Fíli.1 He was the leader of the thirteen dwarves who journeyed with Bilbo Baggins to the Lonely Mountain in T.A. 2941.2, 3
Surviving Smaug's attack on Dale and Erebor in T.A. 2770, he went into exile along with his father and grandfather.2, 3
Thorin fought in the Battle of Azanulbizar in T.A. 2799.1, 3
He earned the epithet "Oakenshield" when his shield broke during the battle and he used an oak branch to fend off orcs.1
In T.A. 2941,3
Thorin was resolved to reclaim his kingdom under the Mountain and embarked upon the Quest for Erebor.2
Upon arriving at Lake-town he declared himself King under the Mountain.4
He was mortally wounded during the Battle of Five Armies and died shortly afterwards. He was buried deep within the Lonely Mountain with the Arkenstone and his sword Orcrist laid to rest upon his chest.5
Positions & titlesKing of Durin's Folk T.A. 2850 - T.A. 2941 King under the Mountain T.A. 2941 - T.A. 2941
1 - J.R.R. Tolkien, The Lord of the Rings, Appendix A, "Durin's Folk"
2 - J.R.R. Tolkien, The Hobbit, An Unexpected Party
3 - J.R.R. Tolkien, The Lord of the Rings, Appendix B, "The Third Age"
4 - J.R.R. Tolkien, The Hobbit, A Warm Welcome
5 - J.R.R. Tolkien, The Hobbit, The Return Journey