Curious historical footnote: when the Moors invaded southern Spain, they took this custom with them and the pronunciation changed over the centuries from "Allah, Allah, Allah," to "Olé, olé, olé," which you still hear
Una curiosa nota histórica, Cuando los moros invadieron el sur de España, llevaron esta costumbre con ellos y la pronunciación cambió con los siglos de "Allah, Allah, Allah" a "Olé,