Humayun lost the empire to which Afghan leader before regaining it in 1555?

1. Sher Shah drove Humayun into exile. 2. Humayun sheltered with the Safavid ruler of Iran. 3. He defeated the Surs in 1555 and died a year later. _Source: syllabus Themes in Indian History Part II, Theme 9, Kings and Chronicles: The Mughal Courts._