Latin, camerarius, cubicularius.
Despite the menial nature of the office itself, the chamberlain, or keeper of the king's chamber, was an honourable officer in the royal household, increasingly found in the households of the higher nobility from Domesday Book onwards; the chamberlain was normally a high-ranking noble in his own right.
Like most household offices, that of chamberlain ultimately derives from the Carolingian court. Their recorded history in England goes back only to the mid-tenth century, though the office itself was almost certainly older than that. The chamberlain was normally one of the officers closest to the king, defending his privacy, controlling access to him, and often entrusted with confidential missions on his behalf. One of the Confessor's chamberlains, Hugolin, was buried in the cloister of Westminster abbey. In Domesday Book, several chamberlains were significant landowners both before and after the Conquest.
For further information, see L.M. Larson, The king's Household in England before the Norman Conquest (1904); Simon Keynes, The diplomas of King Aethelred 'the Unready', 978-1016 (1980); John F.A. Mason, 'Barons and their officials in the later eleventh century', Anglo-Norman Studies, vol. 13 (1991), pages 243-62; and David Crouch, The image of aristocracy in Britain, 1000-1300 (1992).