The Cayley crest
In 911 or 912, Rollo the Northman, son of Bernard the Dane, was officially granted by King Charles the Simple land he had seized in Normandy. Rollo appears to be the earliest (reasonably) certain Cayley ancestor. Born in about 860, he was probably the Rolf the Ganger expelled from Norway in about 872 by King Harold Haarfager (Fairhair).
There is a record of Rollo granting the seigneury of Cailly in Normandy to one Ralf in 912, but there is no indication that this Ralf was connected with the Cayleys, and the absence of Ralf as a family name in Norman times suggests that there may be no link.
Rollo’s son William Longsword (Duke of Normandy from 925 to 942) was father of Richard the Fearless (Duke from 942 to 996). Richard, while still married to his first wife Emma, established a liaison with Gonnor, whom he married after Emma’s death. This liaison produced a natural child, Godefroy, who was made Comte d’Eu et de Brionne. Godefroy’s son Gillebert (alive in 970) became Count on his father’s death. Osbern, Seigneur de Cailly by the year 1050, was believed to be a son of Gillebert.
Osbern himself is the first Cayley ancestor with whom an association with Cailly is firmly established. He was also the first of several Cayley benefactors of the Abbey of St Ouen in Rouen. He was still alive in 1107, so for the period he seems to have lived to a good age.
In 1060 a “Vicomte de Cailly” was sent by William of Normandy (the Conqueror) as an ambassador to Edward the Confessor, quite possibly to discuss the succession to the English throne when Edward died. (William was already planning to bid for the English crown.) It is not clear who this “Vicomte” is.
It is likely that Guillaume de Cailly was Osbern’s son, though he may have been of a collateral branch. Guillaume was one of William the Conqueror’s companions when he invaded England in 1066. For those keen on exact descriptions of relationships, Guillaume was probably William’s half second cousin once removed.
One of Guillaume's sons changed his name on marriage to "de Preaux". The de Preaux and Cailly families helds lands in both Normandy and England.
As with many other Anglo-Norman families, loyalties were divided in the years around 1200 when Philippe-Auguste, King of France, fought King John of England and wrested Normandy and other French possessions from him. Two de Preaux brothers fought on opposing sides, one being one of King John's chief commanders - but in the end the family decided that their main interests lay in France. The Cailly family on the other hand had their chief holdings in England and ended up giving their loyalty to the English crown. This did not stop them siding with the barons in a rebellion against King John in 1215.
Partly by marriage the Cailly family became very extensive landowners, with holdings in many counties, though concentrated especially in East Anglia, and more particularly in Norfolk: but the main lands passed out of the family when the senior branch lacked a male heir in 1316. By then a junior branch of the family held lands in Yorkshire, and from this branch the Cayleys of Brompton descend.
One Cayley possession is famed in literature: the mill at Trumpington near Cambridge. The family acquired this in the early medieval period, and it was the setting of The Miller's Tale, one of the bawdiest of Geoffrey Chaucer's Canterbury Tales.