Discussions on Marc Bloch usually focus on The Annales School, his comparative method, or his defence of a distinct historical science. In contrast, I emphasise his seldom-investigated ideas of what historical understanding should involve. I contend that Bloch distinguishes between three different ethical attitudes in studying people and ways of life from the past: scientific passivity; critical judgements; understanding. The task of the historian amounts to understanding other worlds in their own terms. This essay is an exploration of Bloch’s methodology and what historical understanding is needed to do justice to cultures that belong to the past, both conceptually and practically.