The time when Islam took the stage in Makkah, the time when the innocent religious community was subjected to brutal attacks for adopting monotheism. Persia and Rome were the two major powers in the world at that time. The Persians were very interested in fire worship and polytheism, but the Romans were the believers of holy Injeel.
That was when the war between Rome and Persia broke out. Naturally, the Unbelievers in Makkah favored the idolatrous Persians, and the Muslims Romes. Because if Persia win in battle, it will affect the Islamic culture, and idolatry would increase day by day.
But Persia conquered Rome, the Muslims were ridiculed, and unbelievers thought that Islam could no longer grow. At that time, chapters of the Qur'an were revealed for the relief of the believers.
الم * غلبت الروم * في أدنى الأرض وهم من بعد غلبهم سيغلبون * في بضع سنين
(Rome is conquered now, but Rome will conquer them in a few years)
It was the content of that verse, but no one was able to contain it. Because Persia had gained so much power.
Taking advantage of the opportunity, Ubayy ibn Khalaf(one of the leading polytheist) approached Abu Bakr (ra), and discussed its emptiness. At that time, Siddiq said, "If the Qur'an had said so, it would have come true."
On this occasion Ubayyubnu Khalaf bet with Abu Bakr that they would bet ten horses that Rome would conquer Persia within three years. The Prophet knew this and said that the word "bila'a" in the Qur'an could be three to ten, so the bet should be made within ten years. When Siddiq(ra) informed Ubayy ibn Khalaf about this, he told them that it was not a matter of years alone, as it was unlikely to happen with ridicule.Thee situation was deteriorating, the Roman Empire was overthrown, and Emperor Caesar fled the country, eight years after the revelation of the Qur'anic verse, and no change was seen. The whole community of believers panicked, and migrated to Madinah.
Thus, in AD 623, Caesar set out to invade Persia with his army, conquering the commercial territory of Azerbaijan. At last Persian Empire collapsed shortly after the conquest of the region of Azerbaijan. Ten years, the Qur'anic chapters were as true as daylight, and the Roman Empire was victorious. Let the anti-Islamists say that the Qur'an is a fabrication of Muhammad. Those who still disbelieve in the Qur'anic chapters -that prophesied that something that was decreed impossible ten years ago- would be possible can be linked to Abu Jahl, who, despite knowing that the Qur'an is true, walked away with his fingers in his ear, thinking that he would lose his status.