Early Muslim conquests
Visigoth

During the migration period, the Germanic Visigoths had traveled from their homeland north of the Danube to settle in the Roman province of Hispania, creating a kingdom upon the wreckage of the Western Roman Empire. The Visigothic state in Iberia was based around forces raised by the nobility whom the king could call out in the event of war. The king had his gardingi and fideles loyal to himself, while the nobility had their bucellarii. The Visigoths favored cavalry with their favorite tactics being to repeatedly charge a foe combined with feigned retreats.

The Muslim conquest of most of Iberia in less than a decade does suggest serious deficiencies with the Visigothic kingdom, though the limited sources make it difficult to discern the precise reasons for the collapse of the Visigoths.
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