How are past events explained by teachers in the classroom, and how do their narrative styles relate to the framework of understanding the past? While analysis in textbooks has been central to the study of history education, the way in which these textbooks are used and explained has not been fully clarified. Through a comparison of American and Japanese history lessons, this study identifies styles of explanation of teachers and explores how the past, present, and future are structured in their narratives.<BR>Observations of history lessons revealed that in Japanese classrooms, teachers explained past events chronologically as a long sequential chain, and focused on historical figures' emotional states, which were not treated in the textbooks, to link the events in the chain. In this framework, “empathy” was considered the ability most needed for understanding history.<BR>In American classrooms, by contrast, teachers re-framed historical events in a causal order. They first defined a certain event as an effect and asked students to find causes. Teacher's questions about why an event happened framed a continuous temporality to show a clear correspondence between cause and effect. In this process, information that did not contribute to the explanation of the effect was eliminated. The identification of causes by looking back from effects was taught as a skill, and “analysis” became the most important ability for understanding history. These two methods of understanding the past, “temporal sequential” order and “causal” order, also influenced the way students thought about the direction of causality and about the future. How history is taught deeply relates to the socialization of cognition. The differences between the two countries suggest the importance of studying teachers' styles of presentation and explanation, in addition to studying textbooks.