The Safavid Empire was founded in the 16th century by Shah Ismail I in the region between the Ottoman Empire and India. It became an important empire along the Silk Road trade route through cooperation with neighbors and conversion to Shia Islam under Ismail I. However, the Safavid ruler was replaced after a military loss to the Ottomans, but the empire was revived and expanded under the leadership of Abbas I through improvements to the military and infrastructure. The Safavid Empire eventually declined due to a lack of strong successors over time.