The Franks, under King Charles’s son Louis the Pious, to whom his father has assigned the Franks’ southwestern front, had laid siege to Barcelona in 800.

Local Christian rulers aid the Franks and, after a series of struggles, Louis occupies Barcelona (with Ausona) on December 28, 801, thus securing Frankish power in the borderland between the Franks and the Moors.

The newly appointed Count of Barcelona, one Bera, now becomes the principal representatives of Frankish authority in the Spanish March, or Marca Hispanica, a buffer zone beyond the province of Septimania, created by Charles I in 795 as a defensive barrier between the Umayyad Moors of Al-Andalus and the Frankish Kingdom.

The March includes various outlying smaller territories, each ruled by a lesser miles with his armed retainers and who theoretically owes allegiance through the Count to the Emperor.

The rulers are called counts; when they govern several counties they often take the name duke.

Counties formed in the ninth century at the eastern end of the Pyrenees as an appanages of the Counts of Barcelona include …