Peaceful existence under the sway of Rome continued until the beginning of the fifth century, when the Goths first forced their way across the Pyrenees. During the first barbarian occupation, the Suevi seized Gallicia and Tarraconensis, the Alans Lusitania and Carthaginensis, and the Vandals Betica or Andalusia. The irruption of the Visigoths changed this settlement; the Alans and the Vandals crossed to Africa, and the Suevi occupied Betica and Lusitania. The Visigothic Empire left but slight traces in Portugal, slighter even than in Spain, and the Portuguese nobility do not, like the Spanish, invariably lay claim to Gothic descent. Ethnologically the Gothic element is very slight in Portugal, though the country passed under the rule of the Visigoths during the reign of Ataulphus, who married the sister of the Roman Emperor Honorius, and remained part of their dominion for three centuries. While the Roman rule left so many traces of its existence, and entirely modelled the language and civilization alike of Spain and Portugal, that of the Visigoths, which lasted nearly as long, left hardly any traces at all. The cause is to be found in the natural assimilation of a race in a low state of civilization to the status of a higher race. The number of Romans who actually settled in the peninsula must have been very small, yet the Celts adopted their language and civilization, while the conquering Visigoths, on the other hand, adopted the religion and civilization of the people they had conquered. The Visigothic power reached its zenith in the reign of Euric at the end of the fifth century, and afterwards steadily declined, being torn by internal dissensions, and especially by the great struggle between the nobility and the rulers of the Christian Church. It was the leaders of the latter party, Count Julian and Archbishop Oppus, who invited the Mohammedans from Africa into Spain, and in fighting against them, Roderick, the last Visigothic king, was killed near Xeres, at the battle of the Guadelete, in 711.