The de Trafford family can trace their ancestry back to the 11th century. The main branch was founded by Randolphus, who owned several manors in Lancashire and Cheshire. He died around 1050, sixteen years before the Norman Conquest. As with the bulk of the Anglo-Saxon lords, the family initially resisted the Norman invaders, and they defeated Hamon de Massey near Mobberley in Cheshire. However, they afterwards made peace with the Normans, and were granted a pardon. They later took the Norman-style name "de Trafford" in reference to their manor of Trafford, now part of Greater Manchester.
The 14th century was important for these manorial lords, in receiving acclaim from the Crown. Henry Trafford died in 1395, holding the manors of Trafford and Stretford, together with part of the manor of Edgeworth, and leaving a son and heir Henry, six years of age. This son died in 1408, the manors going to his brother Edmund, known as the Alchemist, from his having procured a licence from the king in 1446 authorizing him to transmute metals. Sir Edmund, at Eccles in 1411, married Alice daughter and co-heir of Sir William Venables of Bollin, and thus acquired a considerable estate in Cheshire, which descended in the Trafford family for many generations.
Cecil Trafford was made a knight at Hoghton Tower in 1617. He was at first, like his grandfather, a Protestant and a persecutor, but afterwards, about 1632, became a Catholic. As a recusant family, they faced persecution and, in 1638, accordingly, the king seized a third of his estates and granted them on lease to farmers. Siding with the king on the outbreak of the English Civil War, he was seized and imprisoned by Roundheads and his estates were sequestered. His sons are mentioned as serving some of the English Interregnum at Rome and Douay. In 1653 Sir Cecil begged leave to transact under the Recusants Act relating to the sequestered two-thirds of his estates.
Sir Cecil died in 1672. His eldest son Edmund died twenty years later, and was followed by a brother Humphrey, who was accused of participation in the fictitious plot of 1694, and sympathized with the rising of 1715. Around this time the family left their original home, which they occupied since 1017, moving to Whittleswick Hall, which they renamed Trafford Hall. Humphrey was succeeded by his son and grandson, also both named Humphrey. The last of these died in 1779 and was succeeded by his relative John Trafford of Croston, who died in 1815. During this time, owing to the laws concerning religion all offices of state had been closed against Catholics, who had therefore to dwell quietly on their estates. The family's prospects improved after the Catholic Emancipation, and in 1841 John Trafford was created a Baronet by Queen Victoria. Sir John later obtained royal licence to change the family name from "Trafford" to "de Trafford", thus restoring it to its original mediaeval form.
The arms of the family consist of a red griffin on a silver background, blazoned argent, a griffin segreant gules. Their crest is a man in the act of threshing a wheatsheaf with a flail. This refers to a legend in which a member of the family escaped the Roundhead army by pretending to be a thresher. They have two mottoes: "Now Thus", and "Gripe Griffin Hold Fast".