A slightly later and more prolonged phenomenon was the growth of nascent boroughs in association with royal and baronial castles.
There followed a series of political manoeuvres from which one man, the King's brother-in-law, Simon de Montfort, emerged as a somewhat improbable champion of English and baronial interests.
But the feudal system also allowed for Church functionaries, for instance the abbots of powerful monarchies, to adopt something of a baronial role.
The highest price paid to date for a baronial title is £250,000 for the feudal Earldom of Arran, which comes with several thousand acres.
But baronial powers were largely abolished after the 1745 Jacobite rebellion.
From the early years of Edward II's reign until the coup in Nottingham, members of the nobility had usually been forced to take either the side of the crown or the baronial opposition.
Most of our evidence concerning the heraldry of twelfth-century baronial families comes from surviving seals.
In the evening it's back to the baronial hall for a documentary about George's old production company, Mancunian Films, and the Formby episode from The South Bank Show.
Not surprisingly, the baronial movement took on some of the characteristics of a crusade.
The last thing they wanted was to allow baronial power to take root in the Indies.