After his defeat at Chausa, Humayun reached Agra and called all his brothers for consultation. Kamran offered to fight against Sher Khan with 20,000 troops but Humayun rejected the offer because he did not trust his brother. He was prepared to accept the help, if Kamran would lend him his troops.
The difference between the two brothers could not be composed and consequently Kamran left with his troops for Lahore. Somehow, Humayun managed to raise an army and the effective fighting strength of the Mughal Soldiers was about 40,000. In May, 1540 was fought the Battle of Kanauj. In this battle, the Mughal Artillery did not play any part as it could not be taken to the front when Sher Khan started the attack. In the case of Kanauj also, Humayun d’d not start the attack for full one month. The Battle of Kanauj was fought and lost. Humayun , ^came a fugitive and Sher Khan became the master of Agra and Delhi.
“Thus began a weary exile which lasted for nearly 15 years and was endured only by the greatest fortitude and perseverance, though it was constantly prolonged by Humayun’s inability to command respect and faithful allegiance.”
About the Battle of Kanauj, Michael Prawdin says that “This was more than a lost battle, this was a total defeat from which no quick recovery was possible. With all his artillery and war equipment in the hands of Sher Shah, Humayun could not even think of defending his capitals or forts. He did not dare to delay in Agra as Sher Shah had immediately despatched a strong detachment in pursuit of him. He avoided entering the town himself and sent Hindal into collect the valuables and the royal family.”