Battle of Chausa was fought near Buxar. Humayun was badly defeated and Sher Khan adopted the title of Sher Shah. Humayun barely escaped with his life from the battle field.
Mubarak Shah was the second ruler of the Sayyid dynasty which ruled the Delhi Sultanate after the fall of the Tughlaq dynasty. He succeeded his father, Khizr Khan to the throne in 1421 CE.