The Architects that created the Hagia Sophia were Isidore and Anthemius of Miletus and Tralles respectfully. Both were professors of geometry at the University of Constantinople. They were hired by Emperor Justinian I in the fourth century to complete the original Hagia Sophia.

Isidore was a mathematician and earlier a physics teacher in Alexandria and the moved to Constantinople. Anthemius was from an educated family with four brothers and himself is known for his work on Hagia Sophia and his work with mirrors and mathematics.

From 1847-1849 Abdülmecid II hired Gaspare and Guiseppe Fossati to renovate the now mosque after it was changed in 1453 (see History). The brothers revised the decorations, inside and out, they also straightened columns, and they consolidated the dome and vaults. They also added the calligraphic roundels to Hagia Sophia.