Gandalf splits off prior to Helm's Deep and heads to Isengard. Then they head to Helm's Deep, and the Battle of Helm's Deep happens. Aragorn, Legolas, and Gimli meet Gandalf, who is now 30% whiter.Merry and Pippin escape and meet Treebeard and the Ents. The Uruk-hai are attacked by the Rohirrim.Aragorn, Legolas, and Gimli put Boromir into a funeral boat and follow the Uruk-hai who have Merry and Pippin.They are abducted, and taken towards Isengard. Boromir dies in battle defending Merry and Pippin.There they meet Galadriel, and receive gifts. Gandalf is separated from the rest of the Fellowship while battling a Balrog. In Moria, they are attacked by Orcs and a Balrog. They fail to cross the mountains via the pass of Caradhras, so they travel through Moria.At the end of the year, the Fellowship of the Ring is formed and departs Rivendell. Aragorn and the hobbits arrive in Rivendell.The hobbits arrive in Bree at the Prancing Pony.A few months later, they depart with Pippin joining them. This begins the quest, Frodo and Sam make plans to depart. Gandalf visits Frodo, and determines the ring is The One Ring.

He's held there, and questioned by Gandalf, who then leaves for the Shire. Aragorn captures Gollum and turns him over to King Thranduil of Mirkwood.He's tortured for information on The Ring. 3017 - Gollum is captured by Sauron's forces.3004-3008 - Gandalf visits Frodo periodically, presumably to keep his eye on the new Ringbearer.

Sometime late this year Gandalf suspects that Bilbo's ring is The One Ring. Frodo and Merry find the ring amongst Bilbo's possessions. Left behind, on purpose, is The One Ring. He announces his plan to leave The Shire and does so. Let me know what events you'd like me to add. All events take place during the Third Age. The long answer is distilled from this extremely thorough chronology, here's a rundown. Most of the action happens over the course of 3 years. The passing of the ring from Bilbo to Frodo takes place far in advance of most of the story.

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