In 1711 Usbek leaves his seraglio in Isfahan to take the long journey to France, accompanied by his young friend Rica. He leaves behind five wives (Zashi, Zéphis, Fatmé, Zélis, and Roxane) in the care of a number of black eunuchs, one of whom is the head or first eunuch. During the trip and their long stay in Paris (1712–1720), they comment, in letters exchanged with friends and mullahs, on numerous aspects of Western, Christian society, particularly French politics and Moors, ending with a biting satire of the System of John Law. Over time, various disorders surface back in the seraglio, and, beginning in 1717 (Letter 139 ), the situation there rapidly unravels. Usbek orders his head eunuch to crack down, but his message does not arrive in time, and a revolt brings about the death of his wives, including the vengeful suicide of his favorite, Roxane, and, it appears, most of the eunuchs.
The Chronology breaks down as follows:
- Letters 1–21 [1–23]: The journey from Isfahan to France, which lasts almost 14 months (from 19 March 1711 to 4 May 1712).
- Letters 22 –89 : Paris in the reign of Louis XIV, 3 years in all (from May 1712 to September 1715).
- Letters 90 –137  or [supplementary Letter 8 =145]: the Regency of Philippe d’Orléans, covering five years (from September 1715 to November 1720).
- Letters 138 – 150 : the collapse of the seraglio in Isfahan, approximately 3 years (1717–1720).
The first edition of the novel, which consists of 150 letters, appeared in May 1721 under the rubric Cologne: Pierre Marteau, a front for the Amsterdam publisher Jacques Desbordes whose business is now run by his widow, Susanne de Caux. Called edition A, this is the text utilized in the recent critical edition of Lettres persanes for the complete works of Montesquieu published by the Voltaire Foundation in 2004. A second edition (B) by the same publisher later in the same year, for which there is so far no entirely satisfactory explanation, curiously included three new letters but omitted thirteen of the original ones. All subsequent editions in the author’s lifetime (i.e., until 1755) derive from A or B. A new edition in 1758, prepared by Montesquieu’s son, included eight new letters – bringing the total to 161 – and a short piece by the author entitled "Quelques réflexions sur les Letters persanes." This latter edition has been used for all subsequent editions until the Œuvres complètes of 2004, which reverts to the original edition but includes the added letters marked as "supplementary" and, in parentheses, the numbering scheme of 1758.