Oldbucks
From Tolkien Gateway
The Oldbucks were an ancient family of Shire-hobbits, who went on to become one of the most well-known families of Shire, the Brandybucks.
Ancestry
Consisting of mainly Stoorish blood, the members of this prosperous family came from the Marish, where they traced their heritage to one Bucca of the Marish, the first Thain of the Shire. Thainship was in the Oldbuck family until 740, Shire Reckoning.
That year, Gorhendad Oldbuck settled across the Brandywine, and the Oldbucks changed their surname to Brandybuck.