Established in 1847 by the Reverend Henry Brereton, the first chaplain of Karachi, as a school for 'English and Anglo-Indo children', it is the oldest private school in Pakistan and the second oldest in South Asia.
Since the 1980s, Karachi Grammar School has expanded from a school with a population of a few hundred students to a large institution that now occupies three sites and teaches more than two thousand students.