The baronage is the collectively inclusive term denoting all members of the feudal nobility, as observed by the constitutional authority Edward Coke. It was replaced eventually by the term peerage.
The term originated at a time when there was only one substantive degree of nobility, that of the feudal baron. The feudal baron held his lands directly from the king as a tenant-in-chief by the feudal land tenure per baroniam. This gave him the obligation to provide knights and troops for the royal feudal army. Barons could hold other executive offices apart from the duties they owed the king as a tenants-in-chief, such as an earldom. Immediately after the Norman Conquest of 1066 a very few barons held the function of earldom, then not considered as a separate degree of nobility per se. An earl was at that time the highest executive office concerned with the administration of a shire. The earl held higher responsibilities than the sheriff (from shire-reeve). In Latin, a sheriff was referred to as vice-comes, meaning a deputy-count, that is to say a deputy-earl, "count" being the Norman-French term for the Anglo-Saxon "Earl". This later developed into the English peerage title of viscount.
The privilege attached to this heavy burden was the right, indeed the obligation, to attend the king in his feudal court, the precursor of parliament, termed the Council de Baronage. It was a standard part of the feudal contract that every tenant was under the obligation to attend his overlord's court to advise and support him, receiving in return his protection from outside hostile forces. Thus the sub-tenants of a tenant-in-chief, the lord of the manor within the jurisdiction of whose manor they lived, were obliged to attend the manorial court or court-baron. The baron had no feudal superior but the king, and thus the king's court was the appropriate place for attendance by the barons, collectively forming the baronage.
Eventually the duties of the executive office of earldom became redundant, being absorbed by the sheriff, and the title of earl became in itself a title of nobility above that of baron, yet the baronage remained the collective term for both degrees, since earls continued nonetheless to hold their lands per baroniam. Possession of a barony was thus the common factor of the baronage. Indeed in the ancient sense of the word baron as simply a tenant-in-chief, all attendees at parliament were "peers", that is to say "equals" (Latin: pares) one to the other in regard to their feudal standing under the king. With the decline of the feudal system and the creation of barons by writ from 1265, that is to say by a personal summons from the king based on the recipient's personal characteristics rather than his form of land tenure, the feudal barony lost its claim as the qualifying factor for nobility, and the barony by writ, or by letters patent from 1388, became altogether personal not territorial. The Further degrees of nobility of dukes, marquesses and viscounts were likewise created by writ and by patent, and the term baronage was no longer adequate to describe all degrees of nobility collectively. Thus was coined the term peerage to replace it.
Yet the ancient usage of the degree of barony as the sine qua non of the nobility continued until the 21st. century. All members of the peerage must be barons, as it were to qualify, for as Hallam stated: "Every earl was also a baron", and in this respect the ancient concept of the baronage survives as the common factor of the nobility. No commoner is ever elevated directly to a higher degree of nobility without the fiction of at the same time being created a baron, enabling him to join the baronage of ages past, which therefore still survives in this theoretical form. Thus the commoner Admiral John Jervis was elevated to the peerage in 1797 as Earl St Vincent, a fittingly high reward for his naval services, at the same time he was created the relatively lowly Baron Jervis. The same was the case in the 1980s on the elevation of the former British prime-minister Harold Macmillan to an earldom, when he was created a baron simultaneously. Such a barony is borne in gross that is to say it is never used by its holder but rather is submerged within his higher title. It may however emerge when used by his heir apparent to take a seat in the House of Lords by writ of acceleration, that is to say where such son has particular political skills which the government of the day wishes to make available to itself in parliament. It may also be used without any legal or political substance as a courtesy title by the eldest son of an earl or higher noble.