

Kloos lives in New Hampshire with his family and has been employed as "a soldier, a bookseller, a freight dock worker, a tech support drone, and a corporate IT administrator". He drew upon these experiences in his military science fiction.

Kloos served in the West German military as a junior NCO in 1989. In 2019, his short stories, Lucky Thirteen and On The Use Of Shape-Shifters In Warfare, were adapted as part of the Netflix anthology series Love, Death & Robots.Īftershocks, the first book in a new series, "The Palladium Wars," was released in July 2019. Lines of Departure was nominated for the 2015 Hugo Award for Best Novel on a slate organized by the " Sad Puppies", a group of "right-leaning science fiction writers." In reaction to this, Kloos withdrew the novel from consideration for the award. The reviewer considered the second novel, Lines of Departure, to be an improvement in that it reflected a critical outlook towards powerful, centralized government that was often absent in leading works of the genre such as Robert Heinlein's Starship Troopers. Reviewing the first novel, Terms of Enlistment, io9 described it as sticking close to the conventions of the genre, focusing on "guns, acronyms, hard-ass drill sergeants, explosions and battles on alien worlds".

Featuring the protagonist Andrew Grayson, they are set in a future in which a Western and an Eastern power bloc are at war with each other and with an alien threat. Kloos is best known for his Frontlines series of military science fiction novels. Born in Germany, Kloos lives and works in the United States. Marko Kloos is a German author of military science fiction and high fantasy.
