What region of India was a Mongol vassal state?

The region of India that was a Mongol vassal state is primarily associated with the Delhi Sultanate, particularly during the rule of Alauddin Khilji in the early 14th century. The Mongol Empire exerted influence over parts of northern India, and while the Delhi Sultanate resisted direct Mongol control, it engaged in tributary relations at times. The Khilji dynasty managed to repel several Mongol invasions, maintaining a degree of autonomy despite the Mongols' attempts to dominate the region.