Precedence over the title of “Little Hagia Sophia” is given to the Church of Saints Sergius and Bacchus, though, many claim the title. The name change is representative of the structure’s transformation into a mosque. The origins of the structure can be traced back to Justinian, who began planning the church during his time at the Palace of Hormisdas (though the time frame is much debated) where he and his (future) wife Theodora lived from 518 until then emperor Justin died in 527. Justinian’s motivation for building the structure was politically driven. He was born a peasant, and rising in the ranks, he would encounter many whose lineage was high, which was important to many. Juliana was a major rival, who was the only person alive with lineage to the prior emperor. Both would try to built the most iconic structure’s that they could, and Justinian surpassed her when he built Hagia Sophia.
Observations about the structure lead us to the following:
Minarette and the Portico were Ottoman additions, and (although speculative) an earthquake lead to one capital differing from the rest. There is embankment around much of the church, along with graves that it enclosed. The dome sits on an octagonal plan, and one important thing to note is the proximity there was to the aforementioned Palace of Hormisdas. The courtyard would have been shared by the Basillica of St. Peters as well.
The interior uses two types of columns, both offering different types of support, and relationships between it and the many cisterns of Istanbul. Overall, the structure was quite beautiful, and regardless of its years of construction or planning, I find it a wonderful example of beautiful design.