It seems that every great book out there is getting turned into a movie these days. Part of the reason for this is that better CGI has allowed Hollywood to bring to life imagery that practical effects never could achieve in decades past, while another reason no doubt has to do with the finite amount of creative originality in Hollywood forcing them to turn to outside sources for help.

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Of course, another big reason for the adaptations is that as social morays change, film is able to show more graphic and more experimental content. However, some books are too twisted even for Hollywood. Such is the case with these 10 books about war:

The Whale Road by Robert Low

Author Robert Low is an interesting character, having worked in journalism as a war correspondent since Vietnam and trained in his spare time to perform mounted archery and Viking Age historical reenactments. The Whale Road is the first of the Oathsworn series and it shows all of Low's combined experiences, reading at once like an Icelandic saga and an account of the brutalities of warfare Low witnessed during the Balkans genocides. The savagery of combat and brutal treatment of slave women in peace are unflinchingly depicted here.

The novel follows its young protagonist, Orm Rurikson, from the shores of Western Norway across the northern seas to the wars of the Khazari Empire on the steppes and beyond. He sails with the Oathsworn, a Viking crew led by the famed Einar the Black, as they travel in search of the silver hordes lost with the burial mound of Atilla the Hun.

Cloud of Sparrows by Takashi Matsuoka

Takashi Matsuoka's novel is set in Japan just six years after the country opened its borders to the west.  After surviving an assassination attempt, Lord Genji prepares his household for war in this tale of love, honor, and vengeance, unfolding against the backdrop of the tumultuous changes impacting the country.

The book is unfilmable for two reasons. On the one hand, it depicts battle through the lens of the merciless samurai honor code of bushido, while on the other hand, it frankly addresses the cultural biases between Japan and Western cultures - an examination of xenophobia that would be upsetting to most modern audiences.

The Fifth Season by N. K. Jemisin

The Fifth Season is the first book in N. K. Jemisin's Broken Earth trilogy. This novel is a masterwork of speculative fiction and it won the Hugo Award for Best Novel, as did both of its sequels. It is dedicated to "all those who have to fight for the respect that everyone else is given without question." The sequel, The Obelisk Gate, is dedicated to people "who have no choice but to prepare their children for the battlefield."

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Technically, the novel is contracted for a film adaptation. However, this book is one of those perfect examples of a book that is too literary to be adapted onto the big screen. For example, one of the many nuanced stylistic choices which make it stand out is Jemisin's decision to write one of its three protagonists, a middle-aged mother named Essun, using the second person.

The Religion by Tim Willocks

As the Knights Hospitallers are preparing to be attacked at their citadel on Malta by the armies of the Ottoman Sultan Suleiman the Magnificent, they recruit the atheist arms dealer Matthias Tannhauser to aid them in this epic sprawling novel.

Being an ex-janissary, Tannhauser has close ties to the Ottomans, putting him in the heart of a siege where he has loved ones and enemies on both sides of the walls. The unflinching depictions of battle, late medieval medicine, trafficking, and the Inquisition make this a gruesome read, but its attempt to show the religious complexities of Christianity and Islam make it too high brow for Hollywood.

Blood Meridian by Cormac McCarthy

Cormac McCarthy's Blood Meridian, or The Evening Redness in the West is considered one of the greatest Westerns (or, depending on who one speaks to, anti-Western) ever written. The story is noted for its spare style and nonstop graphic violence as its protagonist joins up with a group of men riding out to collect scalps.

From a tree filled with dead babies that hanging from their branches to the merciless scalping of Native Americans, the violence in this novel is ever-present. While the story is compelling and filled with gnostic motifs and beautiful landscapes, multiple attempts to adapt Blood Meridian into a movie have failed.

Gravity’s Rainbow by Thomas Pynchon

Gravity's Rainbow is one of the Great American Novels. This massive, dense work of post-modernism deals with themes such as the trajectory of rockets fired in World War II, the sexual and occult practices of military and government intelligence units, and the juxtaposition between philosophical high art and pornographic low art.

Gravity's Rainbow is a behemoth of a book, a maximalist look at the events surrounding intelligence and civilian communities during World War II. It is nearly impossible to follow all the events while reading it. Any film adaptation would be incomprehensible.

Hagakure by Yamamoto Tsunetomo

Unlike the other books on this list, Hagakure is not a work of fiction. It is a treatise on bushido written by the samurai Yamamoto Tsunetomo. When Yamamoto's lord, the daimyo Nabeshima Mitsushige, forbid him from committing suicide and following Nabeshima into death, Yamamoto retired, eventually passing on his lessons about life as a samurai, which was compiled into Hagakure.

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This book is not a linear narrative so would not make for a concrete plot, but many of the stories in its pages are incredibly cinematic and would make for interesting short films. It also is the sort of book that passes along techniques for how to best skin an enemy's face, telling readers to treasure such knowledge.

The Camp of the Saints by Jean Raspail

Jean Raspail's The Camp of the Saints is an unapologetically racist novel and has been cited by multiple fascist leaders currently in power as among their biggest influences. The book is about refugees from non-European countries coming to Europe for aid, being greeted with compassion, and then using murdering those who help them as they invade Europe. Its message is that people of color from the Third World cannot be trusted.

Reading The Camp of the Saints offers insights into some of the most bigoted currently views circling around hate groups. Giving the book a bigger platform would be irresponsible.

The Last of the Wine by Mary Renault

Mary Renault's novel The Last of the Wine is a tale of war and romance in ancient Athens during their prolonged wars with Sparta. The novel's protagonist is Alexias, a beautiful young Athenian man, who falls in love with a wrestler named Lysis. Characters like Socrates, Xenophon, and Alcibiades feature heavily throughout the story, bringing the past to life.

This novel was first released in the 1950s and was beloved by the gay community at the time. As a work that addresses Greek philosophy, the realities of maritime combat, pederasty, and consensual same-sex relationships, it handles many difficult themes with sensitivity. Such sensitivity is not what Hollywood is known for when making historical wartime epics.

Onward Towards Our Noble Deaths by Shigeru Mizuki

The last entry on the list is a graphic novel by the late great manga-ka Shigeru Mizuki. The story follows a band of Japanese soldiers in World War II through the end of the campaign in New Guinea as the grunts are ordered to die honorably for their country while the officers hypocritically refuse to do the same.

Mizuki fought for the Japanese Imperial Army in New Guinea, so his lived experiences color the events of the story. While he is known for his stories about yokai, Mizuki wrote about everything from comfort women to the Fukushima Daishi Nuclear Reactor. The current trends of Japanese film tend to encourage the country's rising nationalism or else eschew discussions of politics entirely, making a good adaptation of Mizuki's novel inconceivable.

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