Meriadoc Brandybuck, usually referred to as Merry, was a Hobbit, and one of Frodo's closest friends. He loved boats and ponies and had a great interest in the maps of Middle-earth. He was also related to Frodo several times over.
Merry was born in TA 2982. He was the only child of Saradoc Brandybuck (TA 2940 - FO 11), Master of Buckland, and Esmeralda Took (TA 2936 - ?), the younger sister of Paladin Took, making him first cousins to their son Pippin, who was clearly his closest friend.
Merry was considered the most perceptive and intelligent of the hobbits: for example, even before Bilbo Baggins leaves the Shire, he knew of the One Ring and its power. He guarded Bag End after Bilbo's party, protecting Frodo from the various and often unwanted guests. He also was the force behind "the Conspiracy" of Sam, Pippin, Fredegar Bolger (more commonly known as "Fatty", due to his plump form), and himself to help Frodo. Thus, even before the Quest of the Ring begins, Merry was well prepared and organised; he assembled their gear and brought ponies. His shortcut through the Old Forest did not serve them well, though they were saved by Tom Bombadil, and were not pursued by the Black Riders. At the Barrow-downs, he acquired his sword, a work of Westernesse.