In African Dominion, seasoned Atlantic world historian Michael Gomez centres his analysis squarely on the empires of the Middle Niger River, arguing that scholars must reimagine how they think about Mali and Songhay's role in a global history of the world. Instead of envisioning these polities along the Niger River through a Eurocentric lens that generalizes all African states as decentralized and defines those that had little contact with Europeans as irrelevant, Gomez argues that West African rulers and imperial officials from Mansā Mūsā to Askia Dāwūd carved out a space for themselves in the Arabic-speaking world. These men and women faced East, envisioning the tendrils of their empires spreading through the savannah, the Sahel and the sea of sand, or the Sahara desert. Although there was a great deal of activity on the Niger prior to Mansā Mūsā’s reign over the Mali Empire, particularly at locales such as Gao, as Gomez explores throughout the book, Mansā Mūsā’s pilgrimage to Mecca gave him and his empire the spiritual prestige he needed to become a peer of others in the Arabic world. Mansā Mūsā’s return to Mali was disastrous, but because of his pilgrimage, contemporary scholars revaluated their ideas about the Bilād as-Sūdān, or ‘the land of the blacks’, to which the Arabic world had been connected through the slave trade since the ninth century.

In addition to his primary thesis, Gomez puts forward several important sub-arguments. Using examples such as slavery's role in West African empires, the power of women in those societies, and the rise of Islam, he argues that Mali and Songhay had a greater degree of continuity with the world that developed after Songhay fell to Morocco in 1591 than scholars have previously argued. Women are relatively prominent in this work, although Gomez does point out that many women on the Middle Niger lacked the same degrees of power that others possessed in spaces such as Hausaland, at least officially. Throughout this book, the author makes a concerted effort to focus on the roles of people who found themselves enslaved by the empire, but who could also influence its actions at home and abroad, such as concubines and eunuchs. Gomez also emphatically argues that Mali and Songhay defy traditional interpretations of African states as weak and decentralized; instead, the author argues that these states possessed complicated and forceful national and local administrations that developed experience over hundreds of years. This argument leads Gomez to some interesting places. For example, the author dismisses a traditional historical interpretation of Timbuktu as politically prominent, instead arguing that, while its scholarly community was spiritually powerful, it did not wield the political influence some scholars have ascribed to it.

Although African Dominion is valuable as a history, Michael Gomez's frank discussion with his readers of his lack of sources brings a great historiographical value to the table as well, both for the layperson and the scholar. The author has expanded a scholarly understanding of West African empires well beyond earlier works, even while using many of the same sources. Gomez meticulously explains his reasoning for each argument where another author might skip over these discussions. There is, of course, a downside to this lack of sources, particularly in some of the earlier chapters. At times, the author's reasoning may seem flimsy or poorly substantiated; inevitably, his lack of sources leaves his work with large gaps. For example, Gomez has relatively few resources to talk about taxation in Songhay. Instead of avoiding that topic, he navigates what is available and informs the reader in the process. In fact, Gomez happily discusses each of these many gaps and explains his reasoning behind each one. He used the sources available to him honestly and to the best of his ability; consequentially, he has produced a work that forces scholars to rethink precolonial West Africa. A similarly path-breaking history of empire, Pekka Hämäläinen's The Comanche Empire, was equally ambitious, but where scholars criticized Hämäläinen for largely failing to describe the Comanche Empire's administration, Gomez describes functioning imperial states with exceptional clarity. Even with these source gaps, this book is a field-shaping work.

Michael Gomez has written a tome that generations of people will read. It is a work aimed more at the scholarly community than the layperson, which is unfortunate, as Gomez's ideas have great potential to change how the average person thinks about African history. Overall, African Dominion is an essential work for students of West African history, precolonial Africa and the history of the Arabic world, as well as for the curious person.