[1] She associated her husband as titular Emperor (Philip II), and retained the claim to the empire after his death on 23 December 1332.

During the reign of her niece, Joanna I of Naples, she opposed the marriage of Joan's younger sister, Maria of Calabria, to Charles, Duke of Durazzo.

In 1333, Catherine's son Robert received the Principality of Achaea through an agreement with his uncle, John of Gravina.

Initially ruling through appointed baillis, in summer 1338 Catherine mustered a fleet and took her whole household to Achaea, where she took an active part in its government.

She gave refuge to Nikephoros II Orsini of Epirus, and supported him in his attempt to assert himself in his land against the Byzantine Emperor Andronikos III Palaiologos.