Having just re-read Mr Christopher Nuttall's TWILIGHT OF THE GODS trilogy for the first time I can safely say that one much prefers CHOSEN OF THE VALKYRIES (title of the second novel in this series) as a title for the trilogy; quite frankly one feels the original name gives the Third Reich too much credit.
Thankfully nothing else in these books threatens to put the Nazis on any sort of pedestal; this is a thoroughly ruthless demolition job on a Third Reich collapsing under the weight of it's own inefficiencies even before student protests boil over into outright Revolution, followed shortly by a full-blown Civil War ... and then things go NUCLEAR.
It's a grim, tension-full and violent series that does rather a good job of setting up a credible 'Third Reich Triumphant' timeline (indeed the novels and Mr Nuttall's online articles about the setting make me very interested in trying to fill some of the gaps left by his world-building ... or at least play around in the ample room left for speculation), then demolish significant portions of it and a fascinating contrast with IN THE PRESENCE OF MINE ENEMIES (Explicitly mentioned as an inspiration in an afterword and very gracefully homaged in the story itself by the existence of an 'Ambassador Turtledove').
There's a certain dark humour in the fact that the latter, a novel in which the Third Reich has explicitly conquered the world (as opposed to establishing dominion over Europe, a little bit of Africa and pieces of Asia), actually comes across as slightly less grim than a setting in which there exists a United Nations* explicitly dedicated to preventing the Third Reich from achieving World Domination (and, as the novel explicitly notes, doing even better at that job than even they realise).
*Strictly speaking a 'North Atlantic Alliance' but 'NAA' doesn't have quite the same ring as 'UN', yeah?
Mind you, comparison is odious and both these works have more than enough strengths of their own to make both well-worth reading (Especially as companion pieces); if I prefer IN THE PRESENCE OF MINE ENEMIES it's mostly because in that novel The Reich collapses with a whimper instead of a roar and you just know that Hitler & the Boys would just HATE that so much more than the rather more Wagnerian bloodbath of RAGNAROK.
When choosing between different versions of the Third Reich's collapse, each equally good, always pick the one the Nazis themselves would hate more.