The National Portrait Gallery is the nation’s family album, I realised. It gives us context. It is our way of describing ourselves and our past to ourselves, our way of interrogating and explaining and exploring who we are, inspecting our roots in a way that is more than just looking at the places from which we come. There is landscape, and there is portrait, after all, and they are ways of explaining the orientation of a sheet of paper, and they are the ways we understand who we are: the places we came from, the people we were.