Influence
Influence measures the degree to which your character can make her wishes count in mortal society. In most cases, she's acquired influence through multiple means, including persuasion, bribery, intimidation, direct manipulation of minds and emotions and passing herself off as a mortal when necessary. It takes time to accumulate more than a dot or two of Influence in a community of any size, and high Influence ratings are the realm of vampires who are prepared to spend years or even decades cultivating their position. Nor is Influence license to do whatever strikes your character's fancy. It's always easiest to get institutions to do what they're already inclined to. Constables need little prodding to arrest suspicious strangers or break up illicit operations whose owners haven't been paying bribes lately, for instance, but they require more incentive to go out killing apparently innocent bystanders or trying to arrest the most important civic leaders. Role-playing therefore supports straightforward declarations of Influence use, and more so as the vampire twists the institution's purpose and outlook.
(The exercise of the Influence Background contributes a great deal to the inevitable tainting of institutions in the Dark Medieval world. Vampires are among the legions of darkness against whom preachers and reformers caution, gnawing away at the bowels of society for personal gain and gratification. It takes time to discredit or undermine believers in a cause and replace them with susceptible pawns and leaders who are willing to abandon moral restraint in their sundry pursuits, but then vampires who survive their early challenges have that time. Vampires make the Dark Medieval as well as suffering in it.)
Each level of Influence reduces the difficulty of relevant social rolls by one. Keep in mind that this applies to the field and area in which your character has influence: Influence among the clergy of Provence matters not at all when dealing with the beer brewers of Vienna.
1) Moderately influential: Significant in the affairs of a city or parish.
2) Well-connected: significant in the affairs of a county or diocese.
3) Position of influence: a force to be reckoned with throughout several counties or an archdiocese.
4) Great personal power: a force in the life of a nation or transnational order.
5) Vastly influential: a power behind the throne of the Church, or behind more than one national throne.