In 1576, Tahmasp I died without a designed heir, leading the realm to descend into civil war. At first, the former shah's favourite son, Haydar Mirza, proclaimed himself king with the support of the Ustajlu tribe and the powerful court Georgians. However, he was soon overthrown by the qurchis (the royal bodyguards). After his death, with the support of the majority of the Qizilbash tribes and the endorsement of Tahmasp's influential daughter, Pari Khan Khanum, Ismail Mirza, who was imprisoned by his father for twenty years, was crowned king as Ismail II. The new king's reign turned out to be short and murderous. The long years of imprisonment had left him suffering from paranoia, with the result that he saw enemies everywhere who had to be eliminated. First and foremost, he began mass murdering the members of Ustajlu tribe regardless of whether or not they had supported Haydar Mirza. He also executed people whose only crime was having a position during Tahmasp's reign.; . The young Abbas was directly affected by his uncle's purge when a group of horsemen rushed into his guardian's house, Shah Qoli Sultan, and killed him.
