First published in 1926. Don Juan was a Persian Moslem who became a Spanish Roman Catholic. His description of Persia and his account of the wars waged by the Persians during the sixteenth century considerably add to modern day knowledge of the history of the period. The book describes the Safavi rule as first established, and the system of government set up in the prime of Sháh 'Abbás, as well as being an account of the long journey from Isfahán to Valladolid.
Guy Le Strange's comprehensive introduction places the book in its historical context, as well as providing important information on how the book was written. Many of the inaccuracies of the original text are corrected in translation with references and notes added to the index to guide the reader.