The romans have been defeated.

Within three to nine years. The decision of the matter, before and after (these events) is only with Allah, (before the defeat of romans by the Persians, and after, i.e. the defeat of the Persians by the romans). And on that Day, the believers (i.e. Muslims) will rejoice (at the victory given by Allah to the romans against the Persians),

(It is) a Promise of Allah (i.e. Allah will give victory to the romans against the Persians), and Allah fails not in His Promise, but most of men know not.