The Wolf's Hour
The Wolf's Hour by Robert McCammon follows werewolf Robert Gallatin, a spy for the Allies during World War II. Set right before D-Day, Robert is on a race against time to unravel a Nazi plot before it can doom the Normandy invasion.
Chapters alternate between the hero's fight against the Nazis and flashbacks to growing up in Russia just after the Revolution. He became a werewolf shortly after his parents were killed in the Revolution, so most of the flashbacks deal with him coming to terms with his new abilities and trying to avoid becoming a complete monster.
Transformations are relatively rare in the book as werewolves in this setting age at the same rate as wolves while transformed. While he does make use of heightened senses and often thinks in a more instinctive way, he generally find other ways to deal with problems than changing forms.
The Wolf's Hour was nominated for the 1989 Bram Stoker Award.
The true first edition of this book is a paperback by Pocket Books of New York in 1989. The first hardcover edition was in Britian by Grafton in 1989. That was limited to only 2,000 copies and is the only hardcover edition in English. Hardcover editions in French under the title "L'Heure du loup" were printed in 1990 by Presses de la Citè and were mass produced.
Citation: Information on identifying editions taken from the website for Robert McCammon.