An engaging narrative describes Dante's family background, poetical influences, involvement in politics, experience of exile, isolation from his fellow exiles, support for Emperor Henry VII, and likely places of sojourn and patrons while in exile, among other aspects of his life for which some evidence survives. In this Bemrose assumes little historical knowledge, including a briefing on Guelphs and Ghibellines, an account of the workings of Florentine politics around 1300, a brief biography of Boniface VII, and other background information.
"Warfare was resumed in spring 1303, but the Whites were again unsuccessful. Whether Dante himself was present in the theatre of war is not clear, but Petrocchi has shown that in May or June he left for Verona, another Ghibelline city. Here he stayed until the following spring; whether as part of a White embassy or simply as a political refugee is unclear. At any event the interlude in Verona, away from troubled Tuscany, seems to have been a relatively peaceful time for Dante. His noble host was Bartolommeo della Scala, who appears to have befriended him."
This is interwoven with outline summaries of all of Dante's major works, discussing their connections to his personal situation and intellectual development. Enough background is provided to make this comprehensible to a reader unfamiliar with medieval philosophy and Bemrose makes it engaging by his selection of topics as well as his presentation. Here he is summarising part of De Vulgari Eloquentia:
"Dante goes on to emphasize the essentially, and peculiarly, human nature of language. Angels, those beings immediately above us in the scale of creation, communicate by direct intuition, and thus have no need of language. Nor do animals, who rank immediately below us, since they communicate by instinct. But we, being rational creatures endowed with mortal flesh, need a 'rational and sensible sign' ('rationale signum et sensuale' - I, iii, 2), that is, something which is based on the senses (since it involves speaking and hearing) yet which can convey the contents of one mind to another. That something is language."
There is, in contrast, little on Dante's work as literature or poetry — some discussion of predecessors and the Stilnovist tradition, accounts of poetical exchanges with other poets, and not much else. The summary of the Divine Comedy focuses on biographical, political and historical links and philosophical ideas, rather than on style, structure and language. We're not even told what form its verse takes!
"After this pungent anti-Florentine passage, the picture broadens once more in Canto VII as the three poets pass through the exquisitely beautiful Valley (ll. 73-81) where a variety of European rulers, too busy to have repented before the last, are pointed out by Sordello. Some sit in pairs, and here the emphasis, so typical of the Purgatorio, is on brotherly reconciliation and transcendence of earthly strife. Thus Emperor Rudolf of Hapsburg sits next to his former foe Ottokar II of Bohemia, and Charles d'Anjou is similarly adjacent to Peter III of Aragon. The Valley is typical of Ante-Purgatory as a whole, a region so different in pace and atmosphere not only from Hell, but from Purgatory proper too. It has a lyrical and peculiarly nostalgic quality, with its patient souls quietly waiting, their often violent and agitated lives behind them. It is more like a departure lounge than an internment camp, but without the uncertainty of either."
All quotes are given in English translation as well as in Latin or Italian. These are brief fragments to illustrate the precise wording of ideas or concepts, however, and are much too short to give a feel for language or style.
There is a little on manuscript and textual traditions, with Bemrose touching on debates over the authenticity of some of Dante's letters. And as an ending Bemrose describes the struggle over Dante's remains and Florence's attempts to get those returned from Ravenna. This gives some idea of Dante's fame, but there's no coverage of the reception of his works and ideas or his significance for Italian literature and history.
A New Life of Dante could be read without any previous acquaintance with Dante or his works, but it would make sense for most people to read a translation of the Divine Comedy first, perhaps with a short introduction placing that in its broader context.