Qutb ud-Dīn Tahmtan is one of the most energetic rulers of Hormuz. A great organizer, his rule is marked by the expansion of Hormuz’s commercial power, development of the island of Hormuz itself, and the transformation of Hormuz to the centre of an impressive empire spreading as far east as the coast of India and west as the region of Basra. He was also a brutal military leader. His initial ruler was faced with another claim by Ghiyath ud-Din, the son of Nu’aim of Kish, and an attack on Hormuz which was thwarted by Tahmtan’s generals, Muhammad Surkhab and Ibrahim Sulghur. Tahmtan’s revenge, upon returning to Hormuz from Mūghistan, was complete. The army of Hormuz conquered Kish, arrested all the dicendants of Nu’aim, including Ghiyath ud-Dīn, and massacred much of the resistance in Kish. The captured were moved to Hormuz and later killed, fully incorporating Kish into the kingdom of Hormuz. Further conquests brought Kharg, Andarabi and other islands further west under Tahmtan’s control. By 740’s, Tahmtan was the undisputed ruler of all of the islands of the Persian Gulf and the lord of many of the coastal regions, including Mughestan, Gambrun, Rishahr, Zufar, Qallahat, and Oman.