he returned to China he began his greatest challenge, conquering the
  Empire of Na-Chung. It took three years, and over 60,000 casualties, but
  he was eventually victorious. In 1226, Genghis went to prevent an
  uprising of the defeated Chinese tribes. He was successful, but on his way
  home, he fell off his horse and was fatally injured. He died in August
  1227.
  Genghis Khan conquered more than twice as much land as any other
  person in history, bringing Eastern and Western civilizations into contact
  in the process. His descendants, including Ogodei and Kublai, were also
  prolific conquerors, taking control of Eastern Europe, the Middle East and
  the rest of China, among other places. The Mongols even invaded Japan
  and Java before their empire broke apart in the 14th century. Genghis
  Khan’s Empire was the largest ever established, extending from the
  Caspian Sea to the Sea of Japan, with over 700 tribes and cities under his
  rule.
    In 1228 Multan and Sind were annexed to the Delhi sultanate. But before
this, Iltutmish reasserted his control over Bihar and Bengal. The Sultan also
suppressed the revolts by the Rajasthan chiefs. Between 1226 and 1231 he
reconquered Ranthambhor, Ajmir, Sambhar, Nagaur and Gwalior. In 1234–
35 Iltutmish led an expedition against Malwa and captured Bhilsa. The
conquest of Ujjain was followed by the demolition of the ancient Mahakal
temple. His earlier military expeditions in Badaun, Kanauj and. Banaras
completely undermined the local rajas’ independence.
    Iltutmish was the greatest ruler of thirteenth-century India and a wise
statesman. The receipt of the mansur (letter of investiture) from the Abbasid
caliph in 1229 gave legal status to Iltutmish’s kingship. Iltutmish was
generous to talented people who willingly became pillars of the central
administration.
Rukn-ud-din (April-November, 1236)
Raziya, the most competent among the children of Iltutmish, had been
promoted by her father over her incompetent brothers. In 1231 Iltutmish