History of Spain: Muslim Era and the Reocupation by Christian Kings (8th-
Treatment of non-Muslims
Rise and fall of Muslim power
The etymology of the word “al-Andalus” is dispute. At least three specific etymologies have been proposed.
The name "Andalusia" or "Vandalusia" was traditionally believed to be derived from "Vandal" (the Germanic tribe that colonized parts of Iberia from 407 to 429), however, there is no historical reference to support this.
Another proposal is that "Andalus" isan Arabic language version of the name "Atlantis". This idea has recently been defended by the Spanish historian Vallvé, but purely on the grounds that it is allegedly plausible phonetically and would explain several toponymic facts (no historical evidence was offered). 
The third theory also rejecting the "Vandal" proposal, originated an innovative alternative. The points of departureancient reports that Germanic tribes in general were reported to have distributed conquered lands by having members draw lots, and that Iberia during the period of Visigothic rule was sometimes known to outsiders by a Latin name, Gothica Sors, whose meaning is 'lot Gothland'. However, the Gothic language version of the term Gothica Sors is not attested.
The propose was that *landahlauts (theasterisk is the standard symbol among linguists for a linguistic form that is merely proposed, not attested). Halm (who proposed this theory) then suggested that the hypothetical Gothic language term gave rise to both the attested Latin term, Gothica Sors (by translation of the meaning), and the Arabic name, Al-Andalus (by phonetic imitation). However, Halm did not offer evidence (historical orlinguistic) that any of the language developments in his argument had in fact occurred.
History of Spain: Muslim Era and the Reoccupation by Christian Kings (8th–15th centuries)
By 711 Arabs and Berbers had converted to Islam, which by the 8th century dominated all the north of Africa. A raiding party led by Tariq ibn-Ziyad was sent to intervene in a civil war in the Visigothic kingdoms in Iberia.Crossing the Strait of Gibraltar, it won a decisive victory in the summer of 711 when the Visigothic king Roderic was defeated and killed on July 19 at the Battle of Guadalete. Tariq's commander, Musa bin Nusair quickly crossed with substantial reinforcements, and by 718 the Muslims dominated most of the peninsula. The advance into Europe was stopped by the Franks under Charles Martel at the Battleof Tours in 732.
Caliph Al-Walid I paid great attention to the expansion of an organized military, building the strongest navy in the Umayyad era. It was this tactic that supported the ultimate expansion to Spain. Caliph Al-Walid I's reign is considered as the apex of Islamic power.
The rulers of Al-Andalus were granted the rank of Emir by the Umayyad CaliphAl-Walid I in Damascus. After theUmayyads were overthrown by the Abbasids, some of their remaining leaders escaped to Spain under the leadership of Abd-ar-rahman I who challenged the Abbasids by declaring Cordoba an independent emirate. Al-Andalus was rife with internal conflict between the Arab Umayyad rulers and the Visigoth-Roman Christian population.
The first navy of the Emirate was built after the humiliating Viking ascent ofthe Guadalquivir in 844 when they sacked Seville. In 942, pagan Magyars raided as far west as Al-Andalus.
In the 10th century Abd-ar-rahman III declared the Caliphate of Cordoba, effectively breaking all ties with the Egyptian and Syrian caliphs. The Caliphate was mostly concerned with maintaining its power base in North Africa, but these possessions eventually dwindled to the Ceuta province....