The lands of Europe in the middle ages use a form of government known as the feudal system. In each kingdom, everyone but the king has a ruling lord above him, to whom he owes loyalty and service in exchange for land and protection. The king awards land grants, called fiefs, to the nobles (chiefly the barons) and sometimes to the church (archbishops and bishops) in return for the payment of taxes and the provision of military service by knights and soldiers. Beneath the king, the hierarchy in descending rank includes nobles, knights, clergy, merchants, tradesmen, peasants and serfs. More details on the feudal system are available here
At the time of the Albion campaign, England and large parts of France are ruled by King Henry II. These lands form a commonwealth of seven independent, sovereign states, loosely bound to each other under the rule of a single man. This makes Henry one of the most powerful rulers in Europe. He travels extensively throughout his lands, and in practice England is governed by the Chief Justiciar, Richard de Luci, and by the barons, archbishops and bishops who rule large parts of the country in the King’s name.
In the north-east of England, where part of the Albion campaign is based, the most powerful local rulers are Baron Henry de Percy and the Archbishop of York. Other influential nobles include Baron Umfraville of Prudhoe and the Bishop of Durham. Further north, the troubled kingdom of Scotland is ruled, at least notionally, by King William the Lion.