After the death of Babur in 1530, his son Humayun succeeded him.
Unlike Babur, Humayun did not command the respect and esteem of Mughal nobility.
The Chaghatai nobles were not favourably inclined towards him and the Indian nobles, who had joined Babur’s service, deserted the Mughals at Humayun’s accession.
The newly established Mughal empire had two centres of power – Humayun was in control of Delhi, Agra and Central India, while his brother Kamran had Afghanistan and Punjab under him.
Humayun felt that the Afghans were a bigger threat.
He wanted to avoid a combined opposition of Afghans from east and the west.
At that time Bahadur Shah had occupied Bhilsa, Raisen, Ujjain and Gagron and was consolidating his power.
While Humayun was besieging Chunar in the east, Bahadur Shah had started expanding towards Malwa and Rajputana.
In such a situation Humayun was forced to rush back to Agra (1532–33).
Bahadur Shah attacked Chittor in 1534.
Chittor had strategic advantage as it could provide a strong base.
It would have helped his expansion in Rajasthan particularly towards Ajmer, Nagor and Ranthambhor.
Humayun’s long absence from Agra resulted in rebellions in Doab and Agra and he had to rush back.
Mandu was now left under the charge of Mirza Askari, the brother of Humayun.
During the period when Humayun was busy in Gujarat to check Bahadurshah, Sher Shah started consolidating himself in Bihar and Bengal.
Sher Shah invaded the Bengal army and defeated them in the battle of Surajgarh.
Sher Shah started attacking Mughal territories of Banaras and beyond.
Sher Shah captured Gaur (1538) the capital of Bengal.
Sher Shah attacked Humayun at the bank of the river and defeated him.
Sher Shah declared himself as an independent king.
Humayun’s brother Kamran moved out of Agra towards Lahore leaving Humayun with small force.
Sher Shah defeated Humayun in the battle of Kannauj (1540).
By 1545 he had established himself as the supreme ruler from Sindh and Punjab to whole of Rajputana in the West and Bengal in the East.
He died in 1545 in an accidental blast of gun powder.
In 1555 Humayun conquered Agra and Delhi and established himself as the emperor of India.