The Red Occupation

They returned to punish Earth.

In a fractured future, Earth and its Martian colonies no longer share a common destiny. Solar storms sever all contact between the two planets. Left to fend for themselves, the Martian settlers feel forsaken, fostering a resentment toward their home planet.

While Earth claws out of a Dark Age, those on the Red Planet evolve into something new. Calling themselves Marthinians, they embrace an austere martial creed that calls for a holy crusade against Earth.

After six centuries, the Marthinians return to Earth not as prodigal children but as conquerors to eradicate their former home planet's fragmented realms. Their Purge Ships first annihilate floating castles that guard American settlements in the Transylvanian Mountains and the tribal lands of the allied Vosgiens.

But conquest gives way to occupation when the invaders discover long-abandoned, highly coveted antigravity factories buried beneath Earth's surface. A handful of realms are spared as vassals to provide a constant supply of slave laborers to work and die at the excavation sites.

Yet, from a secreted castle and a salt-veined mine, and operating in the city shadows of Islambol, an insurgency arises, igniting a war between twin worlds with irreconcilable destinies.

THE BOOK OF RUIN SERIES
BOOK 1: The Book of Ruin (Winner of the 2020 Indie Reader Discovery Book Award for Science Fiction)
BOOK 2: The Flashfall Sword (Recommended by Indie Reader and Readers' Favorite) 
BOOK 3: RangerKnights
BOOK 4: The Last Skinweaver
BOOK 5: In the Time of the Flash
BOOK 6: The Red Occupation