In 1210, Qutb al-Din Aibak died unexpectedly in Lahore while playing polo, without having named a successor. To prevent instability in the kingdom, the Turkic nobles (maliks and amirs) in Lahore appointed Aram Shah as his successor at Lahore. A group of nobles, led by the military justiciar (Amir-i Dad) Ali-yi Ismail, invited Iltutmish to occupy the throne. Iltutmish marched to Delhi, where he seized the power, and later defeated Aram Shah's forces at Bagh-i Jud. It is not clear if he was killed on the battlefield, or put to death as a prisoner of war. Iltutmish's power was precarious, and a number of Muslim amirs (nobles) challenged his authority as they had been supporters of Qutb al-Din Aibak. After a series of conquests and brutal executions of opposition, Iltutmish consolidated his power. His rule was challenged a number of times, such as by Qubacha, and this led to a series of wars. Iltutmish conquered Multan and Bengal from contesting Muslim rulers, as well as Ranthambore and Siwalik from the Hindu rulers. He also attacked, defeated, and executed Taj al-Din Yildiz, who asserted his rights as heir to Mu'izz ad-Din Muhammad Ghori. Iltutmish's rule lasted till 1236. Following his death, the Delhi Sultanate saw a succession of weak rulers, disputing Muslim nobility, assassinations, and short-lived tenures.