What are the five biggest centers of Sufism?

Context: Sufism in Bangladesh is more or less similar to that in the whole Indian subcontinent. India, it is claimed, is one of the five great centers of Sufism, the other four being Persia, Baghdad, Syria, and North Africa. Sufi saints flourished in Hindustan preaching the mystic teachings of Sufism that easily reached the common people, especially the spiritual truth seekers in India. Sufism in Bangladesh is also called pirism, after the pirs or teachers in the Sufi tradition.

Answer: The five main centers of Sufism are India, Persia, Baghdad, Syria, and North Africa.