Answer:
Empress Theodora.
Explanation:
Theodora (497-548) was a higly influential figure in the emperor´s court. Her intelligence and political skills helped her win husband Justinian´s trust and admiration. She used power to promote her own interests through social and religious policies. She is seen as the most powerful woman in the history of Byzantium.
The most important decision that he made was that he wanted to rebuild the St. Peter's Basilica and create a new one, much greater and larger and better. That's why he got Bramante to do the design, but eventually he was changed for Raphael.