Mongolia is both a physical frontier and a site of political and moral rupture in the novel. Its open steppe exposes the limits of military maps and borders, while the surrounding history of Japanese expansion, Soviet power, and the Nomonhan conflict turns the region into the setting for Lieutenant Mamiya’s wartime ordeal and his later rejection of political certainties.

The Frontier and Its Military Importance

In 1938, Lieutenant Mamiya was assigned to command a small escort for Yamamoto, a civilian hired by the army to investigate Mongolian life and customs in Manchukuo. Mamiya’s own military role concerned the western border and the Khalkha River: he had studied the region’s topography and was expected to improve the army’s maps while helping the mission proceed. The party also included Hamano, an experienced soldier, and Corporal Honda, whose importance to the assignment was not yet clear to Mamiya.

The maps available for the Hulunbuir Steppe and the border with Outer Mongolia were crude. Making the frontier official was politically risky, since both the Soviet Union and Outer Mongolia were alert to border violations and earlier disputes had turned violent. The Kwantung Army was already committed to the war in China and lacked the forces for a major confrontation with the Soviet Union; it therefore preferred to leave the northern and northwestern boundaries unresolved. The resulting uncertainty was not simply a cartographic shortcoming but a political expedient.

At the same time, the army needed accurate maps in case that uncertainty became war. Combat maps had to record where troops could camp, where artillery could be placed, how long infantry would need to march, and where water and horse feed could be obtained. The mission’s topographical work therefore overlapped with intelligence gathering, including exchanges with the Kwantung Army’s intelligence section and the military secret service in Hailar. Military planning depended on details that the vast landscape and unresolved frontier made difficult to establish.

Landscape and the Limits of Orientation

After five days of preparation, the party travelled by train from Hsin-ching to Hailar, continued by truck past the Khandur-byo Lamaist temple, and reached a Manchukuo Army observation post near the Khalkha River. The journey covered about two hundred miles through a region without recognizable landmarks. Mamiya tried to check his map against the land, but the grass-covered mounds and unbroken horizon offered little basis for locating their position beyond estimating it from travel time.

The steppe also unsettled Mamiya’s sense of himself. He describes its scale as oceanic: under a sky in which the sun’s passage was the only visible change, his mind seemed to spread into the surrounding space until it became difficult to keep it anchored to his physical self. The landscape thus resists the map’s promise of precise position and becomes, in his recollection, a setting where ordinary boundaries between person and environment grow unstable.

War, Occupation, and Collapse

The apparent calm of Japanese officers’ life in Hsin-ching existed alongside a widening war. Mamiya recalls that Japan’s war in China was becoming increasingly costly and that relations with the United States were deteriorating, even while officers continued to drink and visit cafes. That contrast makes the frontier’s apparent remoteness deceptive: the border was part of a larger imperial conflict whose consequences were already gathering.

When the Soviet advance later threatened Hsin-ching, the Kwantung Army had been depleted by the southern war and could no longer defend Manchukuo effectively. Its leadership withdrew the main force, leaving border garrisons and Japanese civilian settlers exposed; Chinese soldiers in the Manchukuo Army deserted or revolted rather than fight the Soviets for Japan. The capital was left in a political vacuum as the puppet emperor and his family fled. Mongolia’s borderlands were therefore not a distant margin of the story but part of the collapse of the military and political order Japan had established in Manchukuo.

Violence and the Rejection of Ideology

Mamiya’s experience in Mongolia became inseparable from violence. He recalls witnessing the skinning carried out by a Russian officer and his Mongolian subordinates and being thrown into a Mongolian well. He later concludes that these experiences, alongside the violence he had seen in Manchuria, left him unable to believe in political systems or the people who claimed to act for them. His account connects Japanese imperial practices with Soviet oppression without treating either as an abstract doctrine: both become legible through the people harmed in their name.

The story of Boris Gromov extends that connection beyond the Mongolian border. A former NKVD major, Gromov had been sent to Ulan Bator in 1938 to organize the Mongolian secret police on the NKVD model and suppress suspected opposition. After the Battle of Nomonhan, he was recalled to Moscow and later assigned to occupied Eastern Poland, where his torture practices earned him the name “Boris the Manskinner.” Mongolia thus marks an early stage in a career of political terror that continues elsewhere, while Mamiya’s recollections make the region a lasting source of both historical knowledge and personal disillusionment.