This substantial work, a revised version of the author's doctoral dissertation submitted to Marmara University in 2000, represents the most comprehensive study to date of a crucial period in Iranian history. With the conversion of the Ilkhan Ghazan to Islam, a new phase in Mongol rule in Iran opened, one which attempted to establish the Ilkhanate in the traditions of its Iranian and Muslim predecessors. As Özgüdenli rightly observes (p. 40), although a number of important articles have been written, largely by Western scholars, regarding aspects of Ghazan's conversion and subsequent rule, Ghazan has yet to receive detailed monograph treatment. This is hardly for a lack of sources, and Özgüdenli's study is richly documented with references both to the primary sources and the scholarly literature in Western languages, Persian and Turkish. The first section of the book (pp. 1–41) surveys these sources, taking account of numismatics and travellers' accounts as well as the chronicles, above all in Persian, which form the basis for the study of Mongol Iran.

The main part of the book is divided into five sections which attempt to paint a comprehensive portrait of the social, political and economic aspects of Ghazan's rule as well as providing an overview of such information as we have about Ghazan's private life and personality. The first section (pp. 49–108) offers a chronological narrative of Ghazan's early career as a prince, from his birth in Mazandaran in 1271 as the first son to Arghun until his accession to the throne in 1295. This section discusses his childhood and education, and his appointment as governor of Khurasan on the accession of his father to the Ilkhanate in 1284 where he had to struggle to suppress the revolt of the amir Nawruz, who subsequently became his ally and an important influence on him. Ghazan's conversion to Islam is also discussed (pp. 92–103), and Özgüdenli rejects for lack of evidence the thesis that he converted to gain the support of Muslims for his successful attempt to seize the throne. Rather he sees his conversion as a consequence of “amir Nawruz's influence and his own internal psychological conditions” (p. 103).

The second section discusses political developments at home and abroad during Ghazan's reign, starting with the administrative appointments made by Ghazan on his accession. Özgüdenli then deals with the various rebellions Ghazan faced (prince Suka and Barula in 1296, Balatu in 1297, Nawruz in 1297, Sülemiş in 1298–1299), before discussing his manoeuvres against the Ilkhanate's Mamluk rivals over 1299–1304 (pp. 137–69). The third section (pp. 171–223) deals with Ghazan's relations with other rulers – both local ones within the Ilkhanate as well as foreign powers. The Karts, the atabegs of Yazd, the Qarakhitays of Kirman, the atabegs of Lur, the Shabankara and the Salghurids of Fars were among the local rulers who maintained their positions as vassals of the Ilkhans, as were the Seljuks of Rum and the Georgians, whom Özgüdenli treats as a separate category (“vassal states”), although it is not entirely clear such a distiction would have held much meaning for the Ilkhans. Chapters also deal with relations with the Mamluks, the Byzantines, and other Mongol states such as the Golden Horde, the Chaghatayids and the Great Khans in China. As the concentration is exclusively on political history, the latter section (pp. 215–17) in particular is rather thin, which is a pity given the important research of Thomas Allsen and others on cultural links and which deserves to have been given greater prominence.

The fourth section is by far the longest in the book (pp. 233–360) and deals at length with the reforms of the work's title. As Özgüdenli admits, the Islamic sources describe the domestic political developments of Ghazan's time rather as a move towards instituting justice – in accordance with the duty of an ideal ruler – rather than as a reform, both internal and external crises forced the Ilkhanate to try to adapt, and Özgüdenli argues these reforms affected “every branch of the state and social life” (p. 239). Özgüdenli depicts Ghazan as wholeheartedly adopting the Middle Eastern/Iranian customs of settled life in place of his ancestors' nomadism and, through his choice of titles, trying to depict himself as a conventional Perso-Islamic ruler (pp. 240–41). Özgüdenli also surveys Ghazan's reforms in the bureaucracy and administration (pp. 255–69), in economics (pp. 269–85) through adjustments to the state and sultanic treasuries and to the coinage, which was now to some degree standardized, and above all to taxation (pp. 285–97). New irrigation works were intended to improve agriculture, and efforts were made to encourage deserted villages to be repopulated. Tabriz was given new walls, just outside which Ghazan built a new settlement, Ghazaniyya (pp. 303–05). In the military, reforms were aimed at lessening the capacity of individual commanders to act independently and thereby potentially threaten stability, and the system of iqta‘ (land-grants) for paying the soldiery, well known from pre-Mongol times, was reintroduced. Özgüdenli sees iqta‘s as having been ıntended to introduce nomadic Mongol soldiers to settled life and agriculture (p. 311). The encouragement of Islam as a basis for law did not, however, as Özgüdenli admits (p. 332) mean that the old legal code of the Mongols, the yasa, was set aside. Ghazan's reforms in religion are discussed surprisingly briefly, with just two pages (pp. 333–34) on the replacement of Buddhism with Islam and little more (pp. 334–36) on Ghazani's dabbling with Shiism. In his concluding discussion of the impact of the reforms, Özgüdenli points to the contrast between sources produced at the Ilkhanid court, such as the work of the famous bureaucrat Rashid al-Din, which argue Ghazan's innovations had a profound effect, and local sources, which point to continuing unrest and instability which the more centralized Ilkhanate was still unable to remove (pp. 355–56). The bureacuracy and state system remained too weak, in Özgüdenli's analysis, to implement such an all-embracing package of reforms in an effective and lasting manner (pp. 356–57).

The fourth and final section of the book is divided into two parts, the first (pp. 361–89) discussing Ghazan's death, burial and tomb near Tabriz, today destroyed, and the second (pp. 390–416) his wives, chidren, and personality.

Özgüdenli's book is a solid contribution to the study of Mongol Iran, and offers a useful summary of existing scholarship and the historiographic tradition on Ghazan. Its emphasis on the reforms is at times in danger of obscuring the many continuities – the continuing use of the yasa, for instance, could have done with more detailed discussion – and its concentration on political and administrative history at the expense of religion and culture more generally are perhaps matters to be rectified in a future study. Nonetheless, this is a useful work that serious students of Ghazan will wish to consult.