The rebel Umayyad officer Ibn Marwan, leading a host of Muladis and Mozarabs, had returned to Mérida and rebelled against Emir Muhammad I of Córdoba in 868 After a heroic resistance of several years, he had received honorable terms of surrender from the Emir.

Muhammad orders the walls of Mérida destroyed, but awards to Ibn Marwan …

…the territory surrounding Badajoz, which he either founds or re-founds, and begins to fortify.

Ibn Marwan, hearing of an impending attack by the Emirate forces, had fled northwards from Badajoz,settling in the castle of Karkar (now Carquere, near present Lamego, Portugal).

Afterwards, at Ibn Marwân's request, King Alfonso III of Asturias had sent him auxiliary troops and the combined army had defeated the Emirate forces.

Returning to Badajoz, now a well fortified city, he establishes his rule throughout the whole of the Al'Garb Al'Andalus, "The West", the name given by the Moors of Iberia to the modern region of Algarve and, by extension, to most of Portugal, during their rule of the territory.

Ibn Marwan and the Founding of Marvão (876–877 CE)

Between 876 and 877 CE, the rebel leader Ibn Marwan constructs a fortified stronghold in present-day Portugal, which later becomes known as the Castle of Marvão.

By the 10th century, the site is referred to as Amaia de Ibn Maruán or Fortaleza de Amaia, reflecting both its strategic importance and its connection to Ibn Marwan, a leader known for defying the Umayyad Emirate of Córdoba and establishing semi-independent territories in western Iberia.

Al-Mundhir is able to expel the rebel emir Ibn Marwan from Badajoz in 884.