Horizon in the Middle of Nowhere

There is no reliably verifiable, widely available information confirming that the 2011 anime titled "Horizon in the Middle of Nowhere" is based on a specific standalone “book.” It is most commonly linked not to a single book in the narrow sense, but to the Japanese light-novel series Kyoukaisenjou no Horizon.

The work

• Title: Kyoukaisenjou no Horizon (境界線上のホライゾン)
• Format: light novel series
• Author (original story): Minoru Kawakami

What the book is about (high level, not a retelling of the anime)

It is a large-scale science-fantasy/alternate-history saga set in a world where humanity suffered a collapse, lost its route back to the stars, and attempts to “reconstruct” world history by reenacting major eras and events as part of an overarching project of atonement and restoration. The narrative foregrounds competing political blocs, ideologies, and assigned “historical roles,” and explores the fallout when a critical error causes the boundaries of the constructed system to fail.

The author

Minoru Kawakami is a Japanese novelist known for very dense worldbuilding, heavy terminology, and a complex multi-faction structure.

How closely the anime matches the book

A detailed, source-backed scene-by-scene comparison is not readily available in accessible references. Generally, for adaptations of such expansive light novels, the core setting and major turning points are retained while explanations, internal mechanics, and many secondary threads are compressed or simplified to fit runtime. As a result, fidelity tends to be strong at the “foundation” level (world rules and central conflicts) but weaker in fine-grained detail (terminology, motivations, and political/historical nuance).