Battle of Kannauj:
The major victory of Sher Shah Suri over Humayun was in the Battle of Kannauj which took place in 1540. This battle marked a significant turning point in the history of the Mughal Empire.

Background:
Humayun, the Mughal emperor, faced a formidable challenge from Sher Shah Suri, the Afghan ruler who had risen to power in North India. Sher Shah Suri had already defeated Humayun in the Battle of Chausa in 1539, and the Battle of Kannauj was a crucial confrontation between the two rulers.

Key Points:
- The Battle of Kannauj was fought near the Ganges River in present-day Uttar Pradesh.
- Sher Shah Suri's forces were well-prepared and strategically positioned, leading to a decisive victory over Humayun's army.
- Humayun was defeated and forced to flee, losing his empire to Sher Shah Suri.
- This victory established Sher Shah Suri as the ruler of North India, marking the beginning of the Sur dynasty.

Impact:
The Battle of Kannauj had far-reaching consequences for the Mughal Empire. Humayun's defeat at the hands of Sher Shah Suri led to his exile from India for several years, during which he sought refuge in the court of the Safavid Empire in Persia. It was only after Sher Shah Suri's death in 1545 that Humayun was able to regain control of the Mughal Empire and reclaim his throne.
In conclusion, the Battle of Kannauj was a major victory for Sher Shah Suri over Humayun, reshaping the political landscape of North India and setting the stage for future conflicts between the Mughals and the Sur dynasty.