I want to know the answer to the following question:
Where did the majority of the concepts of Mary's birth show themselves the most ?
All the background I'm provided with is that "Although the doctrine of Mary's Immaculate Conception appears only later among Latin (and particularly Frankish) theologians, it became ever more manifest among Byzantine theologians reliant on Gregory Nazianzen's Mariology in the Medieval or Byzantine East.". Is that enough to answer the question?
Answer: yes