The Battle of Chausa, fought in 1539, was the pivotal clash after which Sher Khan assumed the prestigious imperial title ‘Sher Shah Alam ul Adil’. In this battle, Sher Khan’s forces launched a surprise attack on Humayun’s camp, resulting in a crushing Mughal defeat. This victory not only established Sher Khan’s military superiority but also allowed him to formally declare himself the sovereign of a nascent Afghan empire, issuing coins and having the khutba read in his name, thereby challenging the Mughals’ legitimacy.