Short answers, pulled from the story.
Ismail I declared himself Shahanshah of Iran in the year 1501 when he marched into the city of Tabriz. This event marked the beginning of the Safavid dynasty and a revolution that redefined the religious and political landscape of the Middle East.
The Battle of Chaldiran in 1514 marked the end of Ismail I's invincibility and the beginning of a three-hundred-year struggle between the Safavid Empire and the Ottoman Empire. The Ottoman army defeated Ismail's forces using artillery, which shattered his belief in his divine status and led to internal tribal rivalries.
The ghulams were Christian slaves from the Caucasus region, primarily Circassian, Georgian, and Armenian converts to Islam, recruited by Shah Tahmasp I to serve as royal guards and soldiers. This policy created a new military slave system loyal only to the shah, allowing Shah Abbas I to build a standing army of nearly 40,000 soldiers and centralize control.
Shah Abbas I recaptured Baghdad and eastern Iraq from the Ottomans by 1616 after building a new army equipped with 500 cannons. This military success was part of his strategy to restore the empire and recover western territories lost to the Ottomans.
The Safavid dynasty officially ended in 1722 when an Afghan army led by Mahmud defeated government forces at the Battle of Gulnabad and besieged the capital of Isfahan. Shah Soltan Hoseyn abdicated and acknowledged Mahmud as the new king of Iran, leading to the division of Iranian territories by the Ottomans and Russians.