Tahmasp I was born on the 22 February 1514 to the previous Shah Ismail I, who died from psychological damage after Selim I defeated him in one of the Perisian Wars. Eventually Tahmasp I himself would be attacked by Selim's son Suleiman the Magnificent and had to gave up Baghdad during the Ottoman Conquest of Persia. He came to the throne aged 10 and caused a regency battle between the Turkish Qizilbash who were the supporters of his power. Eventually he took power and created a new layers of society, filled by Caucasians from the northern part of his empire. His enterprise was undermined during the 1568 invasion and lost of everything west of OTL Iran. Both leaders contracted an illness, it killed Suleiman in a month, but Tahmasp got an infection from a wound later and spend his last years in a vegetative state. So his son became regent during 1571.
He married his cousin Begum, a Circassian woman Agha, and multiple Georgian woman, totaling 10 wives. His had these children: