What is a “ban” in medieval lordship?

The story behind the answer

In medieval usage, the ban (from Latin bannum) was a lord’s coercive authority to issue binding orders, summon men for military service, and preside over courts—enforcing judgments with fines or harsher penalties. It was the core of jurisdictional power, distinguishing mere landownership from public authority in a world where royal power was often fragmented.

Originating as a royal prerogative under the Merovingians and Carolingians, the ban devolved to counts and seigneurs, forming the backbone of “banal lordship.” From it flowed obligations like using the lord’s mill, oven, or winepress (banalités), and the very term banlieue originally marked the area under a lord’s command. This differs from narrower fiscal rights (taxes and tolls), forest and hunting privileges, or property confiscations, all of which could exist without the broader judicial and command powers implied by the ban.