In 1220-21 a d they appeared on the north-west frontier for the first time in the reign of lltutmish under the leadership of Chengiz Khan but the infant Muslim empire was saved from the fury of Chengiz Khan, the leader of the Mongols, due to the diplomacy of lltutmish.
Before accepting Islam, the Mongols were the followers of Buddhism and were deadly enemies of the Muslims. They destroyed several Muslim kingdoms in Central Asia and killed innocent persons like sheep and goats. Hence their entry into India was considered a bad omen hut anyhow it was averted. Later on, the pressure of their invasion over Punjab and Sindh increased and they captured the territory upto river Ravi.
The Khaljis had to face their first invasion during the reign of Sultan Jalaluddin Firoz Khalji, who could not prove his strength against them. When Alauddin ascended the throne of Delhi, the Mongols wanted to conquer India. They tried to dethrone Alauddin Khalji, the usurper, and therefore they made some quick expeditions into India one after the other.
They not only disturbed the peace of Punjab but also tried to establish their authority over Delhi and Doab. They were supported by Khokhars and the Afghans who joined their army out of greed for the booty. The dissatisfied nobles also helped them during their raids.