Eventually, Emperor Andronikos II Palaiologos and his son and co-ruler Michael IX had the Catalan leader, Roger de Flor, assassinated with his entourage in April 1305.
In July, the Byzantine army, comprising a large contingent of Alans as well as many Turcopoles, confronted the Catalans and their own Turkish allies near Apros in Thrace.
Despite the Imperial Army's numerical superiority, the Alans withdrew after the first charge, whereupon the Turcopoles deserted en bloc to the Catalans.
Prince Michael was injured and left the field and the Catalans won the day.
The Catalans proceeded to ravage Thrace for two years, before moving west and south through Thessaly, to conquer the Latin Duchy of Athens in 1311.