A seigneurial borough was an administrative division of urban government within a manor of medieval England, that granted a town's citizens or burgesses rights of burgage tenure and a degree of self-government under a charter or prescription granted by the Lord of the Manor. Unlike fully incorporated boroughs, which received their privileges directly from The Crown through a Royal Charter and thus had "no lord but the King", seigniorial boroughs remained dependent on local manorial authority.
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Seigneurial borough Wikipedia(Text) CC BY-SA