Iran was converted to Shi'a Islam under the Safavid Dynasty, but despite having considerable influence in Central Asia, particularly what is now Afghanistan, Tajikistan, and the areas around Samarkand and Bukhara in modern Uzbekistan, Shi'a Islam is not widely spread there, being limited mostly to marginalized populations like the Hazaras and the Pamiris. How could Central Asia have become majority Shi'a, and how would that alter the course of history?