The Bloody Red Baron
from the Anno Dracula Series
by Kim Newman
From Wikipedia (tbd)
Set during World War I. The Graf von Dracula, after being expelled from Great Britain in 1897, spread his brand of unstable vampirism (and with it raging lycanthropy) throughout the Russian Imperial Family. He now leads Germany and the Central Powers against the Entente, with vampires—now a part of everyday life—fighting (and dying) on both sides. The Red Baron of the title is the historical ace fighter pilot Manfred von Richthofen, who in this altered history leads a squadron of monstrous flying vampires.
First published in November 1995, The Bloody Red Baron was shortlisted for the Sidewise Award for Alternate History, Long Form.