The book was published in time for the millennium celebrations of the famous (well, once-famous) battle, and it covers much more ground than just the battle. The first chapters provide basic introductions to the Germanic tribes, the Romans, Roman history just prior to the main event etc and most of it is familiar, so there’s time to notice a large number of typos and grammatical slip-ups. (People who cannot tell das and dass apart are a pet peeve of mine)
But these are negligible irritations, forgotten once he gets to the establishment of the Roman province Germania. From here on in the book is fascinating, because he includes lots of recent research and findings from the Kalkriese digs. There was no splendid isolation of the Germanic tribes beyond the Rhine, unpolluted by Roman decadence as the 19th century would have it. The reach of the legions and the incredible amount of material and work they put into the building of a new province, which are obvious from a few recently explored sites and probably represent only a fraction of the actual effort, are simply amazing. I had heard about these whenever findings of new archaeological discoveries went through the press, but to read about it in such detailed, structured form is illuminating. So why did they let it all go to waste? The jury’s still out on that question.
One other big surprise is Tiberius. He’s had a bad press in his afterlife, and I remember him as a rather unsympathetic character from I, Claudius. Here he comes across as the embodiment of (aristocratic) Roman virtues, efficient, competent, patient, dutiful. And either realistic or simply tired of wasting money and lives on the effort of controlling an obscure region without exploitable resources.
Märtin is a meticulous note-keeper which may put off lay readers, but I appreciated this very much. The enormous bibliography is a treasure trove for further reading. However, the annoying typos and misspellings result in less than full marks.

edited for typo ( )