Ismail I, (July 17, 1487 – May 23, 1524), known in Persian as Shāh Ismāʿil, is Shah of Iran (Persia) (1501)and the founder of the Safavid dynasty, which will survive until 1736.

Isma'il starts his campaign in Iranian Azerbaijan in 1500 as the leader of the Safaviyya, a Twelver Shia militant religious order, and unifies all of Iran by 1509.

Born in Ardabil, Iranian Azerbaijan, he is the king (shah) of the Safavid dynasty from 1501 to 1524.

The dynasty founded by Ismail I will rule for over two centuries, being one of the greatest Persian empires after the Muslim conquest of Persia and at its height being among the most powerful empires of its time, ruling all of Iran, Azerbaijan, Armenia, most of Georgia, the North Caucasus, Iraq, Kuwait, and Afghanistan, as well as parts of modern day Syria, Turkey, Pakistan, Uzbekistan, and Turkmenistan at their height.

It also reasserts the Iranian identity in Greater Iran.

The legacy of the Safavid Empire also represents the revival of Persia as an economic stronghold between East and West, the establishment of an efficient state and bureaucracy, their architectural innovations and their patronage for fine arts.

Ismail plays a key role in the rise of Twelver Islam; he converts Iran from Sunni to Shi'a Islam, importing religious authorities from the Levant.

In Alevism, Shah Ismail remains revered as a spiritual guide.

Ismail is also a prolific poet who, under the pen name Khatā'ī (which means "sinner" in Arabic) contributes greatly to the literary development of the Azerbaijani language.

He also contributes to Persian literature, though few of his Persian writings are still in existence.