Frodo's father, Drogo, had left Hobbiton and removed to Buckland to live with his wife's family, and so Frodo was raised in Brandy Hall, the ancestral home of the Brandybucks. He lost both his parents in a boating accident in 2980. He was close to his distant cousin Bilbo, and nine years after the loss of his parents, Bilbo officially adopted him as his heir. At this time, Frodo moved back from Buckland to Hobbiton.
Although Bilbo often referred to Frodo as his 'favourite nephew', he was in fact his first cousin once removed (through his mother), and also his second cousin once removed (through his father). Frodo lived with Bilbo at Bag End for twelve years, and inherited some of his peculiarities. It was said that he would meet with Elves in the woods, for example, and Bilbo allowed him to read his diary of the journey to Erebor. In 3001, Bilbo held the great Birthday Party on 22 September (a birthday Frodo happened to share) and afterwards departed from the Shire, leaving Frodo to come into his inheritance, including (after much persuasion by Gandalf) the Ring.
On 12 April3018, Gandalf returned, having discovered the truth about the Ring, and so Frodo discovered the history behind the One Ring, and the great danger it held. He resolved to leave the Shire with it. To cover his departure, Frodo sold Bag End to Lobelia Sackville-Baggins, and bought a small house at Crickhollow in Buckland, the region where he had been brought up. He departed from Hobbiton with Peregrin Took and Sam Gamgee on 23 September3018, the day after his fiftieth birthday.
The travellers planned to leave the secretly through the Old Forest on its eastern borders, but they soon discovered the dangers of the lands outside the Shire. On the banks of the Withywindle, they were attacked by the malignant Old Man Willow, and their journey would have come to an swift end if not for the aid of a mysterious and powerful stranger: Tom Bombadil. After their adventures in the Forest, and a brief stay in Tom's house, they set out once more.
Again, their plans went wrong almost immediately. Lost in a fog, they strayed into the Barrow-downs, and were quickly captured by one of the Barrow-wights that dwelt there. Again they were saved by Tom, and finally found their way the East-West Road, along which they travelled in relative safety to the township of Bree. It was later discovered that Aragorn was looking out for Frodo on the road, and had begun to trail the Hobbits as they emerged from the downlands.
In a dell beneath Weathertop, disaster struck. The Black Riders discovered the sheltering Hobbits and attacked, leaving Frodo with a desperate wound to his shoulder. Aragorn used his powers of healing as he could, but it was beyond even his abilities to cure the poisoned wound. Scrambling on through the hills with the wounded Frodo, they made their slow way towards Rivendell and safety.
Frodo and Asfaloth crossed the Ford as the Black Riders paused before entering the waters of Bruinen. On the brink of succumbing to his Morgul-wound, Frodo slipped into the Wraith-world for a moment, as the Nazgûl started to approach. With a sudden roar, the river waters surged into flood through the powers of Elrond and Gandalf. The Black Riders were washed away and, safe at last, Frodo finally fell into unconsciousness on the banks of the river. After twenty-four days of journeying in the Wild, he had brought the Ring to Rivendell at last.
The derivation of Frodo's name is explained in Tolkien's Letters (No 168, dated 1955), where he also explains that '...it had mythological connexions with the legends of the Golden Age in the North.' This seems to be a reference to King Fróði of the Danes, whose reign was legendary for its prosperity and fruitfulness.