The Byzantine-Seljuq wars are a series of decisive battles that shift the balance of power in Asia Minor and Syria from the Byzantine Empire to the Seljuq Turks.

Riding from the steppes of Central Asia, the Seljuk Turks replicate tactics practiced by the Huns hundreds of years earlier against a similar Roman opponent but now combining it with newfound Islamic zeal; in many ways, the Seljuq Turks have resumed the conquests of the Muslims in the Byzantine-Arab Wars initiated by the Rashidun, Umayyad and Abassid Caliphate in the Levant, North Africa and Asia Minor.Today the Battle of Manzikert is widely seen as the moment when the Byzantines lost the war against the Turks; however the Byzantine military was of questionable quality before 1071 with regular Turkish incursions overrunning the failing theme system.

Even after Manzikert, Byzantine rule over Asia Minor does not end immediately, nor are any heavy concessions levied by the Turks on their opponents — it will take another 20 years before the Turks are in control of the entire Anatolian peninsula -- and not for long, either.During the course of the war, the Seljuq Turks and their allies attack the Fatimid Caliphate of Egypt, capturing Jerusalem and catalyzing the call for the First Crusade.

Crusader assistance to Byzantium is mixed with treachery and looting, although substantial gains are made in the First Crusade.

Within a hundred years of Manzikert, the Byzantines will have (with Crusader assistance) successfully driven back the Turks from the coasts of Asia Minor and extended their influence right down to Palestine and even Egypt.

Later, the Byzantines will be unable to extract any more assistance and the Fourth Crusade even leads to the sack of Constantinople.

Before the conflict peters out, the Seljuqs will manage to take more territory from the weakened Nicaean Empire until the Sultanate itself is taken over by the Mongols, leading to the rise of the ghazis and the conclusive Byzantine-Ottoman wars.