Theodore was the son of general Alexios Branas and of Anna Komnene Vatatzina. He was probably born in Adrianople, where his family held hereditary lands. In 1193, according to the chronicler Alberic of Trois-Fontaines, Theodore became the lover of the dowager empress Anna, then aged 22; they did not marry because in marrying a commoner she would have lost her dowry. She was the daughter of King Louis VII of France by his third wife Adèle of Champagne, and the sister of Philip II of France; she had originally come to Constantinople to be betrothed to Alexios II Komnenos, but Alexios was murdered by his co-emperor and regent Andronikos I Komnenos in 1183. She was then married to Andronikos, and was widowed on his violent death in 1185.