Anna embarked on an ambitious project of uniting the houses of Epirus and Constantinople by marrying her daughter Thamar to Michael IX Palaiologos, Andronikos II's son and co-emperor.
This sealed the alliance with Naples, and Charles II's intervention through his vassals Count Riccardo Orsini of Cephalonia and Prince Florent of Achaea helped contain the Byzantine advance.
An alliance was concluded and sealed by the marriage of young Thomas to Anna Palaiologina, the daughter of the co-Emperor Michael IX Palaiologos, Andronikos' granddaughter.
In the meantime Charles II sent troops into Epirus, but they were repulsed and the Epirotes advanced into the Angevin lands in the western Balkans, recovering Butrint and Naupaktos in 1304–1305.
A new Angevin invasion in 1307, aiming to overthrow Anna [4] ended with a compromise by which Philip of Taranto was ceded many of the fortresses that had been retaken by the Epirotes in the previous war.