The First Anglo-Afghan War of 1839-1842 was one of the most disastrous conflicts in the history of the British Empire. It caused the death of thousands and the annihilation of the Army of the Indus. Yet this defeat came after a successful invasion. In analyzing the actions of officials and officers of the British imperial state and the East India Company leading up to and during the invasion, I will argue that these actions served to securitize British India. Securitization is a process by which an actor takes a series of steps to persuade an audience that a specific referent object faces a critical and existential threat. I contend in this thesis that the need for security was used to justify, in the eyes of both British and Indian audiences, the continued territorial expansion and military dominance of the British in India and its borderlands.