Shadows of the Past - The Great War of the Worlds, #1

It's 1915, twenty years after the Martian invasion chronicled in the War of the Worlds failed. The aliens left behind advanced technology and weapons, and now humanity is on the brink of a catastrophic war. Caught in the middle of the chaos are two unlikely heroes: Emil Zimmerman, a young German soldier, and James Brogan, an introverted radio engineer. Emil dreamed of escaping his small village and making his way to the big city, but finds himself in the trenches fighting for an army that indiscriminately wields deadly Martian weapons.
Meanwhile, James just wants to be left alone, but is pulled into a web of conspiracy when he's called upon to repair crucial radios on Long Island. As the world hurtles towards the brink of destruction, Emil and James find themselves on a collision course with fate, each struggling to survive and make sense of a new reality. Shadows of the Past is a science fiction, alternate history, survival adventure.
Do you love War of the Worlds by H. G. Wells? Then the thrilling journey of the Great War of the Worlds series is the series you're looking for.