Why have interpretations of the Battle of Rorke's Drift in 1879 changed over time?

History teachers have been talking about the need to teach broad narratives, overview and chronology for a long time. They have also recognised how essential it is for students to have an opportunity to study the ways in which the past has been interpreted, and the reasons why these interpretations have come into existence. This scheme of work seeks to achieve both, getting students to think about a narrative of British imperial decline across the twentieth century, and to relate this chronology to changing interpretations of a nineteenth-century conflict: the Battle of Rorke's Drift in 1879.