"Return of a King: The Battle for Afghanistan", a history of the First Afghan War 1839–42, was published in India in December 2012, in the UK in February 2013, and in the US in April 2013. Dalrymple's great-great-granduncle Colin Mackenzie fought in the war and was briefly detained by the Afghans. Following the publication of the book Dalrymple was called to brief both the Afghan President Hamid Karzai and the White House on the lessons to be learned from Afghan history.