This book's title and subtitle are both problematic. The Byzantines, who had no word for “identity” in today's sense, called themselves Christians and “Romans” (we would say “Byzantines”), but this “identity” was settled long before the reign of Leo VI (886–912). Meredith Riedel also never clarifies why she calls Leo “unexpected.” He was born in 866 to a woman who was concurrently the mistress of Michael III (842–867) and the second wife of Michael's murderer and successor Basil I (867–886). Widely believed to be Michael's son, Leo became Basil's heir only after the death of Basil's son by his first wife. For three years Basil imprisoned Leo on a charge of plotting against him; a month after reluctantly releasing Leo, Basil died in a suspicious hunting accident; and when Leo became emperor, one of his first acts was to give Michael imperial reburial. Despite clear signs that Basil, Leo, and others thought Leo was Michael's son, Riedel concludes “the truth cannot be known” (1).

She argues that Leo's “religious faith, traced through his extensive literary output, transformed Byzantine cultural identity and influenced his successors, establishing the Macedonian dynasty as a “golden age” in Byzantium until the early eleventh century” (1). Without explaining how this transformation established a “golden age,” she admits, “The question of whether the emperor wrote the literary works attributed to him remains difficult to prove definitively” (3). These works are his Tactica, a military manual, his Novels, or new laws, and his Homilies, orations on largely but not exclusively religious subjects. Most of the Tactica is copied from earlier military manuals, while most of the Novels are addressed to Leo's chief minister Stylianus Zaützes, who apparently took a large part in composing them. Though many scholars believe all Leo's writings were mainly rhetorical exercises, Riedel disagrees.

She declares that in the preface of the Tactica Leo gave the work “the force of legislation” (6–7); but he merely compares it to a legal manual, implying not that it was a law but just that it was a manual. Later she says that by using “the word ‘consubstantial’” in his preface “Leo is trumpeting his christological orthodoxy; it was concerning precisely this doctrine that the conflict raged at the Council of Chalcedon in the year 451” (59). She connects “this doctrine” with Leo's wars on the Arab frontier, where many Christians were not Chalcedonian. Here she makes a glaring error, because the formula that the Father and the Son were consubstantial dates from the Council of Nicaea in 325, not Chalcedon, and by Leo's time was accepted by all Christians.

Next she observes that Leo's Tactica indulges in “racial stereotypes” such as that “Arabs cannot fight in the rain,” which “communicate a shared view of the ‘otherness’ of the enemy” (63). But what the Tactica transmits is not racial stereotyping but sound military advice: that the Arabs are formidable antagonists who should be fought in cold and rain because they are less used to cold than Byzantines are and rely more on archery, which wet bowstrings impede. Though Riedel is obviously right that the Tactica shows Christian sentiments while the pagan military manuals it summarizes do not, she fails to demonstrate that it “innovatively presents a cultural identity crafted in opposition to a troubling and persistent [Arab] enemy” (175).

Turning to the Novels, Riedel seems unaware that they must all date before Zaützes died in 899. Thus she repeatedly accuses Leo of hypocrisy because the Novels forbid concubinage and condemn third marriages; but only after being widowed in 899 did Leo marry a third time and, widowed again, keep a concubine and marry her in 906 to legitimize the son she bore him. Even on the assumption that the Novels show Leo's thinking rather than Zaützes's, when they were composed, Leo was happily married to Zaützes's daughter and could hardly know she would die without bearing him an heir. Yet Riedel speculates that the Novels assigned no penalty for concubinage because Leo “himself notably kept a concubine” (116) and that Leo's condemnation of husbands who kept concubines left “a sort of loophole” for himself after he was widowed (127).

The best known of Leo's Homilies is his funeral oration for Basil I. Linking this oration with Leo's reburial of Michael III, Riedel remarks, “Leo's choices to honour in these various ways both of the men who may have been his biological father reveal a young man determined to be blameless in filial piety” (151), adding, “There is also nothing in this speech to indicate any tension between Leo and his father, despite their fraught relationship” (152). Yet Leo could scarcely mention in his funeral oration for Basil that he was not Basil's real son and had plotted against Basil, though Riedel does note that in another homily Leo “includes a somewhat vague confession of his own guilt that triggered his imprisonment” (149). The funeral oration provides no useful evidence for Leo's feelings about Basil.

Riedel's general remarks are especially dubious. In her interpretation of Leo's thinking, “There are no ‘people of God’ or ‘chosen people’ outside Leo's rule” (153); but her formulation is disproved by Leo's procuring a dispensation for his fourth marriage from the Pope, outside Leo's rule. She claims that Leo based his empire's Christian “identity” on its “othering” of Jews, Muslims, and pagans, because “group identities are contingent upon clear differences with others” (166); but by Leo's time Byzantine Christianity was firmly established on its own terms, and depended no more on such “othering” than American democracy depends on “othering” dictatorships. Criticizing Anthony Kaldellis, she declares that Byzantine stability “arose not from an inherited notion of Roman polity, but from the cultural ballast offered by institutional Christianity;” thus Byzantines “drew their collective identity” from Christianity and certainly not “from a single ethnicity or language” (183). Yet Kaldellis is surely right that Byzantine identity depended not only on Christianity but also on Roman tradition and Greek culture. Pace Riedel, none of these was “transformed” by Leo VI.