In the spring of 711, a Muslim army invaded Iberia led by Tariq ibn Ziyad, serving the Arab governor Musa ibn Nusayr, at Guadalete they swiftly defeated Roderick (Luthariq) the Visigoth King and then marched northward to the Visigoth capital of Toledo. Both Latin and Arabic chroniclers record that the Jews of the city “opened the gates of Toledo” to Tariq, who conquered the city
https://www.judaism-islam.com/jews-opene-the-gates-of-toledo/