Haitian soldiers shoot in the air to try to control the crowd as they wait for food to be handed out after Hurricane Matthew hit Jeremie, Haiti, October 18, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

North Korean soldiers keep watch at the bank of the Yalu River, near the North Korean town of Sinuiju, opposite Dandong in China's Liaoning province, September 10, 2016. (Photo by Thomas Peter/Reuters)

Employees wear "No-Face" masks during working hours at a service company in Handan, Hebei Province of China. As a service company, staff must smile to customers every day. On “No-Face Day”, staff wore masks to hide their facial expressions and allow them to relax. No-Face is a character in the 2001 animated movie “Spirited Away”, a silent masked creature who has no facial expressions.

Soldiers, including two recruits who have brought some chickens, at Victoria prepare to board the train for the battle front. (Photo by Hulton Archive/Getty Images)

A German rifleman beside the corpse of a French soldier in a trench at Fort Vaux, France, 1916. (Photo by Hulton Archive/Getty Images)

Soldiers try to attach the balloon to their car, June 1944. (Photo by Jared Enos/Mediadrumworld.com)

A South Sudanese People Liberation Army (SPLA) soldier patrols the streets in Malakal on January 21, 2014. (Photo by Harrison Ngethi/AFP Photo)

A line of soldiers firing handguns during a training session, circa 1920. (Photo by Keystone). P.S. All pictures are presented in high resolution.