Because World War II was a global conflict, the servicemen who fought in it faced astounding extremes on the battlefield. Soldiers stationed in Europe watched the pleasant spring and summer weather give way to numbing, incapacitating cold in the winter — particularly German soldiers engaged in the Soviet campaign of 1941–1943. For most German troops, the bitter Soviet winter was made worse by a lack of appropriate cold-weather clothing, heaters, and other supplies. In addition, heavy equipment that worked fine in warmer temperatures ground to a halt as internal parts froze solid and vehicles sank axle-deep in the slick winter mud. Soviet soldiers didn't have it much better, though for the most part they were better dressed for and acclimated to the winter temperatures.
The European winters were also a harsh surprise for many American troops, particularly those from the South who were unused to such temperature extremes. But unlike the German soldiers on the eastern front, most Allied soldiers in Europe were issued high-quality cold-weather gear.
The servicemen who fought in the Pacific experienced a host of different problems. Rather than bitter cold, they faced suffocating heat and humidity, as well as a wide variety of insects and wildlife that seemed to go out of their way to make life miserable. The combination of heat, humidity, and extreme physical exertion during combat caused many soldiers to become dehydrated. Unfortunately, water reserves were initially limited at many Pacific battle locations, such as Guadalcanal, and soldiers suffered because of it, often going a full day or more without a drink of water.
The Pacific rains, rather than bringing relief, only added to the average soldier's long, hard days. During the monsoon season, it rained almost every day, often heavily. As a result, it became next to impossible to stay dry, resulting in fungal infections and disease from mosquitoes and other insects. For many soldiers who saw long-term duty in the Pacific, a dry pair of socks was more coveted than a pinup of Betty Grable.
Extreme heat was also a hazard for Allied and Axis forces in North Africa, though it was a more insidious dry heat than that experienced in the Pacific. Sweat evaporated as quickly as it formed, reducing its cooling effect and increasing the need for additional fluids. As a result, water was a precious commodity among soldiers doing battle in the desert. Other serious concerns were sunburn and heat stroke, both of which could drop a soldier as quickly as an enemy bullet.
Temperature extremes weren't the only hazards facing soldiers on the battlefield. An astounding array of new weapons — many developed after World War I — posed tremendous threats to exposed soldiers and even those in bunkers. Most devastating were long-range artillery, which could wipe out an army in minutes, and planes equipped with bombs and machine guns, which could be equally devastating.
War has a way of affecting the senses, and soldiers quickly learned that even small battles could be deafeningly loud and frighteningly disorienting. Fear and panic were common emotions in the throes of combat, and it took all the willpower a soldier could muster to keep from fleeing in the face of enemy fire. Some Allied soldiers, unable to take the strain, deserted their posts or shot themselves in the foot to avoid being sent to the front. When discovered, soldiers with self-inflicted wounds were typically court-martialed, and many served time in prison for their actions. German and Japanese soldiers who deserted their posts faced far harsher punishment from unforgiving commanders.