Anna was the daughter of Manuel Angelos Philanthropenos, Caesar and governor of Thessaly.
Her paternal grandfather, or more likely uncle, was Alexios Angelos Philanthropenos, also a Caesar, who was governor of Thessaly from c. 1373 to 1390.
[citation needed] Gulkhan-Eudokia of Georgia, Manuel's first wife and Empress consort of Trebizond died 2 May 1395.
[2] On 4 September of that year, Eudokia, Manuel's sister and the widow of Tadjeddin Pasha of Sinop and Emir of Limnia, arrived from Constantinople at Kordyle with Anna Philanthropene and Theodora Kantakouzene; these women had come to wed, respectively Manuel III and her nephew Alexios.
[3] The ambassador to Tamerlane, Ruy Gonzáles de Clavijo met Manuel III and his family April 1404 while passing through Trebizond, and alludes to Anna Philanthropene as being alive.