On August 26th, the fate of more than 3 peoples was decided; the ancient Roman Empire was to be usurped by a new Islamic Turkic order in the lands from Egypt to Georgia. The ancient Labarum was to be replaced with the Crescent and the Kaaba, and all lands east of the Bosphuros would finally become part of the East. However, it didn't have to be this way. The Turks only narrowly won a lucky battle where the Romans' ancient rivalry proved more the deciding factor of the great clash more than the Martial Skill of Alp Arslan. So, what if history went to the way of the Romans and and not the Turks? Much different than you could possibly imagine.
Part I: 1080-1100 Romanos the Great
At the time of the Battle of Manzikert, the Romans were actually making significant gains against the Muslim world. The Seljuks were at the time just beginning to settle in their recent conquests of Damascus and the Levant, while embroiled in a rivalry with the retreating but certainly powerful Shiite Fatimid Caliphate. At first, little would change. Arp Arslan would lick his wounds, rebuild his army, and continue the ruling of his nation. However, one very important thing that would change is that the Seljuks would not try again. The Battle of Manzikert and the Seljuk war was caused by a reaction to the Roman conquest of Armenia, at a time a vital buffer state for Muslim rulers of the area. Thus, seen that they were defeated, the Seljuks would retreat back to their Levantine and Mesopotamian holdings, while focusing on the much more pressing concern, the Fatimid Caliphate. In our world, the Fatimids won the struggle by taking over Jerusalem in 1098, although this was mostly and handiwork of the "Crusaders" that the Romans had sent in direct correlation to losing Asia Minor. Only to be utilized by the growing Papal reform movement seen with the Cluny system, several reformist Popes into the absolute mass movement that we saw during the High Middle Ages. This would not happen. Instead, the Seljuks and the Fatimids would continue to duel over the Levant, with the Byzantines dealing with internal matters and consolidating the Caucasus.
In Byzantium, the recent civil war caused by the Doukas rebellion would be in this timeline ended on Romanos's side thanks to the influx of troops coming from his recent conquests in Armenia. Thus, Romanos would be able to establish and sustain himself as an emperor, at least for a couple of years. However, one thing to consider that perhaps with the much more tolerating force that would be necessary with a such a vital and different province like Armenia would mean that there is a possibility of anti-heretical revolt by the Clergy and several opportunistic nobles, but thanks to the particularly cruelty by Romanos, a very plausible outcome of the Doukan rebellion is a crackdown in order to scare the other nobles into submission. It can be safe to assume that Romanos would've held on to his position for a very long time, ensuring stability unseen for years. Not that the peasant's lives would be much better, but this means that contenders would think twice before trying to unseat the Basilius Metaliko.
The Muslims were not the only rivals to the Empire. The recent Norman conquest of Apulia and the invasions of Magna Graecia would continue to go forward in this world, even with the Romans defeating the Seljuks, they would still fail to be able to defeat the Normans for the simple reason that it happened earlier than the divergence. However, it is possible that Byzantium could recounquer Apulia, and with the wrathful nature of Romanos already established it is certainly possible. However, it is time for us to finally address the Elephant in the room, the Crusades.
AND WITH THAT IT IS TIME FOR THE END FOR THE FIRST CHAPTER! PLEASE GIVE ME YOUR THOUGHTS IN THE COMMENTS AND LET ME KNOW IF THIS IS SOMETHING YOU WANT TO SEE, IT'S KIND OF HARD WITH SCHOOL AND WORK AND PT TO DO THIS RIGHT NOW, BUT IF SUPPORT IS SHOWN I CAN CERTAINLY CONTINUE IT! THANK YOU FOR READY AND HAVE A PLEASANT DAY.