Bilbo Baggins

Bilbo Baggins is one of the supporting characters in The Lord of the Rings and one of the main characters and the main protagonist in The Hobbit.

Youth
Bilbo was born fifty years before the Quest of Erebor on September 22 in Bag End to Bungo Baggins and Belladonna Took. There, his parents raise him in their hobbit home and their hometown, Hobbiton. However, despite being a Baggins, Bilbo wants adventure as he grows older. As a child, Bilbo often stays out past his bedtime in search of Elves, late after dark while trailing in mud, twigs and fireflies. During one of the Old Took's parties, Bilbo watches Gandalf set off fireworks for his grandfather's parties. One evening, Bilbo approaches Gandalf with his wood sword, playfully hitting the wizard on the sides. Bella approaches the pair, gently chastising her son and apologizes to Gandalf for her son's playful nature. However, the wizard lets it pass by and just ruffles the child's curls. (An Unexpected Journey: Extended Edition)

Time goes on and Bilbo grows up into a young mature hobbit. He is about 24 years old when the Fell Winter hits. At 36 years old, his father dies and eight years later so that his mother. Bilbo later takes ownership of all his parents' possessions, including their family home, Bag End. (The Hobbit: An Unexpected Journey)

Before the Quest of Erebor
At least the year before Bilbo's journey, a meeting between Gandalf and Thorin Oakenshield takes place at Bree, where the former inspires Thorin to reclaim the Lonely Mountain. Gandalf states that he will help Thorin with taking back his Homeland and steal the Arkenstone back. Thorin asks how could they take the stone, as it is with the dragon in his horde. Gandalf reveals they'll need a burglar, knowing with the help of Bilbo Baggins, a Hobbit, to retrieve the Arkenstone. Reluctant to have him in his company, Thorin agrees to meet Bilbo on Gandalf's behest (The Desolation of Smaug).

Before the Battle of the Five Armies
Gandalf warns Bilbo not to underestimate the evil of gold, as it can corrupt even the strongest minds to anyone who lays their eyes on it, except when he looks at Bilbo, Gandalf adds "Almost all," referring to Bilbo's indifference to gold.