As more states require world history for students, there has been an increase in world history course work for teachers. Despite these demands, there has been little examination of world history teachers' knowledge, or what might provide coherence in teaching this vast subject. This gap in the scholarship is compounded by confusion in the field and school subject. Few teachers who teach world history have formal training in the subject; state and national standards vary drastically in content and usefulness; and world historians do not always agree upon the structure and scope of their field. Where, then, can teachers turn to reconcile this confusion when the very places where they might look to build coherence—standards and the field—are themselves in a state of disarray?

This dissertation takes up this question by studying instructional tools, the field of world history, and teachers' understandings about world history. My central purpose is to understand: How can we develop coherence in world history from so much time, space, and events? To address this question I engaged in three connected studies: a content analysis of the Journal of World History; an analysis of standards for world history; and card-sorting interviews with novice and experienced world history teachers.

A central finding in this dissertation rests with conceptual devices I identified in the work of world historians. Explicitly and implicitly, world historians argue for and use multiple but nested units of analysis (comparison, case studies, interregional and global patterns), and different temporal and spatial schemes. In my analysis of standards I found that, although the documents utilized some of these devices, they did not make the process of engaging in world historical thinking apparent.

I also found differences in how experienced and novice teachers used conceptual devices to build meaningful connections between events, construct coherent historical narratives, and relate world historical content to student understandings. By uncovering devices that make world history coherent for historians and describing how teachers thought about applying those features to their pedagogy, this dissertation has implications for teacher educators in using those features for designing instructional tools and preparing teachers.