In the early 21st century, Buddhism has become ubiquitous in America and other western nations, moving beyond the original bodhi tree in India to become a major global religion. During its journey westward, it has changed, adapted to new cultures, and offered spiritual help to many people looking for answers to the problems of life. It is being studied in institutions of higher education, being practice by many people, and having its literature translated and published.

The Historical Dictionary of Buddhism covers and clarifies Buddhist concepts, significant figures, movements, schools, places, activities, and periods. This is done through a chronology, an introductory essay, a bibliography, and over 700 cross-referenced dictionary entries.