In June 1098 Alexios I arrived at Philomelion (modern-day Akşehir, Turkey). While his general, John Doukas, reconquered Roman lands in western Anatolia, the Emperor had marched east via Dorylaeum, the scene of Bohemond's recent victory over the Seljuk Turks.
According to Anna Komnene, her father 'sacked' a number of towns en route. To judge from his line of march, these towns were probably Nakoleia, Santabaris, Hebraike, Kedrea and Polybotos.
Anna's evidence must be questioned. It is uncertain whether these towns were even occupied in 1098; if they were, the population may have considered mainly of Greeks. It seems unlikely that Alexios would have sacked towns inhabited by his own subjects.
Regardless, it is clear that Alexios and John Doukas swiftly recaptured much of the west. The emperor's main purpose was to join the crusaders at Antioch, as he had promised, but at Philomelion he encountered a group of Franks on the run. 
These were Stephen of Blois, William Grandmesnil and Peter of Aups, all heading rapidly in the opposite direction. They warned Alexios that the siege of Antioch had failed, and the crusading army was defeated. This was untrue, but Alexios was sufficiently alarmed to turn back and return to Constantinople. 
The meeting at Philomelion marked the point where the First Crusade ceased to be an imperially managed operation. Alexios continued to supply the crusading army, but from now on the Frankish leaders were in command.