The Umayyad conquest of Hispania (711–718) began as an army of the Umayyad Caliphate consisting largely of Berbers, inhabitants of Northwest Africa recently converted to Islam, invaded the Christian Visigothic Kingdom located on the Iberian peninsula (Hispania). Under the authority of the Umayyad Caliph Al-Walid I of Damascus, and commanded by Tariq ibn Ziyad, they disembarked in early 711, perhaps at Gibraltar, and campaigned their way northward. Tariq's forces were reinforced the next year by those of his superior, the Emir Musa ibn Nusair.
During the eight-year campaign, most of the Iberian Peninsula was brought under Muslim occupation, save for remote areas in the northwest (Galicia and Asturias) and largely Basque regions in the Pyrenees. The conquered territory, under the Arabic name al-Andalus, became part of the expanding Umayyad empire.
The invaders subsequently moved northeast across the Pyrenees, but were defeated by the Frank Charles Martel at the Battle of Tours (Poitiers) in 732. Muslim control of French territory was intermittent and ended in 975.
Though Muslim armies dominated the peninsula for centuries afterward, Pelayo of Asturias's victory at the Battle of Covadonga in 722 preserved at least one Christian principality in the north. This battle later assumed major symbolic importance for Spanish Christians as the beginning of the Reconquista.
Precisely what happened in Iberia in the early 8th century is subject to much uncertainty. There is one contemporary Christian source, the Chronicle of 754 (which ends on that date), regarded as reliable but often vague. There are no contemporary Muslim accounts. What Muslim information there is comes from later compilations, which are much coloured by the writers' sense of what was proper, and by contemporary politics — the most prominent such compilation is that of Al-Maqqari, which dates from the 17th century. This paucity of sources means that any specific or detailed claims need to be regarded with caution.
What are available are a number of stories that might more properly be described as legends. The manner of King Roderic's ascent to the throne is unclear; there are accounts of dispute with the son of his predecessor Wittiza, and accounts that Wittiza's family fled to Tangier and solicited help from there. Numismatic evidence suggests some division of royal authority, with several coinages being struck. There is also a story of one Julian, count of Ceuta, whose daughter was raped by Roderic and who also sought help from Tangier. However, these stories probably date from several hundred years later. Ceuta was also a haven for Arians and Jews avoiding forced conversion to Roman Catholicism.
As to the initial nature of the expedition, historical opinion takes three directions: (1) that a force was sent to aid one side in a civil war in the hope of plunder and a future alliance; (2) that it was a reconnaissance force sent to test the military strength of the Visigothic kingdom; (3) that it was the first wave of a full-scale invasion.
What is clear is that in the early 8th century, an army led by one Tariq Ibn Ziyad crossed from North Africa. Ibn Abd-el-Hakem reports, one and a half century later, that "the people of Andalus did not observe them, thinking that the vessels crossing and recrossing were similar to the trading vessels which for their benefit plied backwards and forwards." It defeated the Visigothic army, led by King Roderic, in a decisive battle in 712 and went on to take control of most of Iberia. The Chronicle of 754 states that 'the entire army of the Goths, which had come with him fraudulently and in rivalry out of hopes of the Kingship, fled'. This is the only contemporary account of the battle, and the paucity of detail led many later historians to invent their own. The location of the battle is not totally clear, but was probably the Guadalete River.
Roderic and the great majority of the Visigothic elite are believed to have been killed. Such a crushing defeat would have left the Visigoths largely leaderless and disorganized. The survivors fled north to Écija, near Seville. The resulting power vacuum, which may have indeed caught Tariq completely by surprise, would have aided immensely the Muslim conquest.
The conquering army was made up mainly of Berbers, who had themselves only recently come under Muslim influence and were probably only lightly Islamised. It is probable that this army represented a continuation of a historic pattern of large-scale raids into Iberia dating to the pre-Islamic period, and that actual conquest was not originally planned. Both the Chronicle and later Muslim sources speak of raiding activity in previous years, and Tariq's army may have been present for some time before the decisive battle. It has been proposed that the fact that the army was led by a Berber, and that the Ummayad Governor of North Africa, Musa ibn Nusayr, only arrived the following year, supports this possibility — the governor had not stooped to lead a mere raid, but hurried across once the unexpected triumph became clear. The Chronicle of 754 states that many townspeople fled to the hills rather than defend their cities, which might support the view that this was expected to be a temporary raid rather than a permanent change of government.
The conquest led to a period of several hundred years in which the Iberian peninsula was Al-Andalus, dominated by Muslim rulers, and with only a handful of small Christian states surviving in the mountainous north. In 756 Abd ar-Rahman I, a survivor of the recently overthrown Umayyad Dynasty, seized power in the province, founding an independent dynasty that survived until the 11th century. Muslim domination lasted longer: until the defeat of the Almohads in the 13th century, after which the Christian Reconquista became irresistible.