Tahmasp (tä´mäsp), 1514–76, shah of Persia (1524–76), son and successor of Ismail and the second of the Safavid dynasty. He successfully repulsed persistent invasions by the Uzbeks. Sulayman I also invaded Persia, continuing the wars between Ottomans and Persians commenced by Selim I. One stage of these wars ended with a peace treaty in 1555. In 1561 an Englishman, Anthony Jenkinson, succeeded in establishing a trade route to Central Asia and Persia across Russia. Continual warfare during the reign of Tahmasp helped bring about internal decline.