The origin of the Roxburghe family dates back to the Kers of Cessford in the 15th Century and the Dukes of Roxburghe have lived at Floors Castle since it was built in 1721.
It is possible that the line in Britain began with two brothers, Ralph and John, originally from Normandy, who passed from England into Scotland in the 13th century. This laid the foundations for the two houses, the descendants of Ralph, the Kerr line, Marquesses of Lothian, and the descendants of John being the Kers of Cessford. There is a Henry Ker, granted a letter of protection for himself and a retinue of 12 men from Edward III in 1363. It is in this period that the name of Ker is listed as being associated with the barony of Auldtounburn. In the early part of the 15th century, the Kers are associated with the Earls of Douglas, the most prominent family in the region until their fall from grace in the middle part of the century.
Though the family can trace its lineage back to the High Middle Ages, family history pertinent to Floors Castle begins with the 5th Earl of Roxburgh, who was made the 1st Duke in 1707. It is useful, for context however, to also consider the line of Earls that began in the early part of the 17th century, to chart the rise of the family from prominent Border Reivers to major players on the national stage.