Civil War between supporter of Wittiza, Count Julian, Arian and Jew with smaller Muslim auxuliaries against supporter of Roderic and the Catholic.
if Charles Martel equivalent is Catholic, after the war he will persecute Arian and Jew harshly. probably expel non-catholic to Ceuta.
ethnic conflict is also possible, if Hispania is christian pennisula. there are byzantine presence on east coast, Berber, Visigoth and native spaniard.