Barons were introduced into England by the Normans; most of whom held that rank in Normandy before the Conquest. Baron literally meant a man, being the King's tenant in chief, i.e. holding his land directly from the King. The burgesses and leading citizens of London were also known collectively as Barons, and this style was allowed them by clerks who wrote the writs of William II and Henry I. The barons of the Cinque Ports are a parallel to the barons of London. In the 13th century they were summoned to the Counsel or Parliament, but at first this did not imply that a successor would necessarily also be summoned to subsequent Parliaments. The more important would probably be summoned, but by the reign of Edward III it became usual for successors to receive writs as a matter of course. Thus the Baronage emerged into a hereditary dignity of the Peerage.
The first baron created BY PATENT was John Beauchamp de Holt, created Baron Kidderminster, by Richard III in 1387 with remainder to his heirs male, but baronies by writ also continued to be created long after this date.
A baron is styled Right Honourable and formally by the Sovereign Right trusty and well-beloved (and counselor when a member if the Privy Council).