Tahmasp I (Persian: طهماسب, Ṭahmāsb or تهماسب Tahmâsb; 22 February 1514 – 14 May 1576) was the second shah of Safavid Iran from 1524 to 1576. He was the eldest son of Ismail I and his principal consort, Tajlu Khanum. Ascending the throne after the death of his father on 23 May 1524, the first years of Tahmasp's reign were marked by civil wars between the Qizilbash leaders until 1532, when he asserted his authority and began an absolute monarchy. He soon faced a long-lasting war with the Ottoman Empire, which was divided into three phases. The Ottoman sultan, Suleiman the Magnificent, tried to install his own candidates on the Safavid throne. The war ended with the Peace of Amasya in 1555, with the Ottomans gaining sovereignty over Iraq, much of Kurdistan, and western Georgia. Tahmasp also had conflicts with the Uzbeks of Bukhara over Khorasan, with them repeatedly raiding Herat. In 1528, at the age of fourteen, he defeated the Uzbeks in the Battle of Jam by using artillery, unknown to the other side.