Born to Saradoc Brandybuck and Esmeralda Took in 2982 of the Third Age, he was an only child. Normally known as Merry, he was called 'Master Holdwine' in Rohan, and was later called 'The Magnificent'.

He was part of the the Fellowship of the Ring. At the breaking of the Fellowship, he and Peregrin were captured by Orcs and carried off. They managed to escape into Fangorn Forest where they met an Ent called Treebeard.

He was there for the storming of Isengard, and later became a knight of Rohan. He rode into The Battle of the Pelennor with a knight called Dernhelm, even though he had been told he would be no use. He then distinguished himself by helping to kill the Lord of the Nazgûl.

After the War of the Ring he lived for a time with Pippin in Crickhollow. He married Estella Bolger and became the Master of Buckland in the year 11 of the Fourth Age.

In the spring of 63 of the Fourth Age, a message came from Rohan that King Éomer wished to see Master Holdwine again. He and Pippin set off, and were in Rohan when Éomer died. They both then went to Minas Tirith, and when they died, their bodies were laid in Rath Dínen with the greats of Gondor.